Acquisition of epithelial–mesenchymal transition phenotype and cancer stem cell-like properties in cisplatin-resistant lung cancer cells through AKT/β-catenin/Snail signaling pathway

Polyhexamethylene guanidine phosphate induces epithelial-to-mesenchymal transition and cancer stem cell-like properties via Wnt/β-catenin signaling in human bronchial epithelial cells

Inhalation exposure to polyhexamethylene guanidine phosphate (PHMG-p), a primary component of humidifier disinfectants, has been linked to interstitial lung disease and potential carcinogenic effects. This study aimed to investigate epithelial cell transformation and the underlying molecular mechanisms by examining the properties of epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs) following prolonged exposure to PHMG-p. Beas-2B human bronchial epithelial cells were treated with 0.125-0.5 µg/ml PHMG-p for over 55 passages, resulting in approximately a 1.2-fold increase in proliferation and a 2-fold enhancement in wound healing, migration, and invasion. Long-term exposure induced morphological changes in Beas-2B, which adopted a spindle-shaped appearance, and displayed enhanced expression of EMT markers, including N-cadherin, Vimentin, Twist, and Snail (approximately 1.5- to 3.5-fold). Culturing these cells in a cancer stem cell medium further confirmed neoplastic transformation and the induction of CSC properties in long-term PHMG-p-treated cells. Additionally, expression levels of CSC phenotypic markers (CD44, CD133, ABCG2, and ALDH1A1) and stemness markers (SOX2, OCT4, Nanog, and KLF4) increased during PHMG-p-induced carcinogenesis. Moreover, increased reactive oxygen species (ROS) production and expression of β-catenin indicated the involvement of these signaling molecules during carcinogenesis. Collectively, our findings suggest that chronic exposure to PHMG-p, even at relatively low concentrations, can induce neoplastic transformation through the acquisition of EMT, stemness, and CSC phenotypes, potentially linked to the endogenous ROS and Wnt/β-catenin signaling pathway.

Tumor β-Catenin Expression Associated With Poor Prognosis to Anti-PD-1 Antibody Monotherapy in Non-small Cell Lung Cancer

Background/Aim

Tumor intrinsic β-catenin signaling has been reported to influence the tumor immune microenvironment and may be a resistance mechanism to immune checkpoint inhibitors in various cancers.

Patients and Methods

We studied the association between tumor β-catenin expression and survival in 50 patients with non-small cell lung cancer (NSCLC) treated with anti-programmed death-1 antibody monotherapy. Tumor β-catenin expression was evaluated by immunohistochemistry.

Results

Patients with positive tumor β-catenin expression (20% of all patients) had worse progression-free survival and overall survival compared with those with negative tumor β-catenin expression. Patients with positive tumor β-catenin expression had reduced CD8+ cell and CD11c+ cell infiltration into tumor nests than those with negative tumor β-catenin expression. RT-PCR of tumor tissue revealed that patients with positive tumor β-catenin expression showed lower gene expression of CD8A, CD4, IFN-γ, BATF3, and CCL4. Knockdown of CTNNB1 tended to increase CCL4 expression, likely mediated by ATF3, in a lung cancer cell line with positive β-catenin expression.

Conclusion

NSCLC patients with positive tumor β-catenin expression that were treated with anti-programmed death-1 antibody monotherapy had poor prognosis.

Mechanistic insights into Yifei Sanjie pill's regulation of EMT to enhance gefitinib treatment effect in NSCLC by in silico analysis and experimental validation

ETHNOPHARMACOLOGICAL RELEVANCE

The Yi-Fei San-Jie pill (YFSJ) is a well-known Chinese medicine that has been used to treat non-small cell lung cancer in China for decades.

AIM OF THE STUDY

Previous studies have shown that YFSJ combined with gefitinib can effectively inhibit the proliferation of gefitinib-resistant non-small cell lung cancer (NSCLC) cell lines by promoting apoptosis and autophagy, but the molecular biological mechanisms involved and whether YFSJ combined with gefitinib can have synergistic effects still need to be further explored. Thus, the present study aimed to establish an in silico and experimental framework to decipher the underlying mechanism by which YFSJ augments the efficacy of gefitinib in treating NSCLC.

MATERIALS AND METHODS

Integrated approaches, including microarray analysis, network pharmacology, RNA sequencing, bioinformatics algorithm analysis and in vivo and in vitro experiments, were applied to elucidate the underlying mechanism.

RESULTS

Analysis of microarray datasets indicated that gefitinib may play a role in the regulation of the epithelial-mesenchymal transition (EMT) of PC9 cells. EMT-related Gene Ontology (GO) terms and the MAPK pathway were found to be enriched in the differentially expressed genes (DEGs), and a decreasing trend was observed in the EMT score. Network pharmacology analysis revealed that the potential NSCLC-related targets of YFSJ also showed enrichment in EMT-related GO terms and the MAPK pathway. Experimental findings demonstrated that combined YFSJ-treated serum and gefitinib treatment significantly inhibited PC9 cell migration and invasion. In addition, the combined treatment dramatically reduced the tumour volume in an animal model. The effectiveness of the combination treatment surpassed that of gefitinib alone in both cell and animal experiments. RNA sequencing analysis revealed significant enrichment of DEGs in EMT-related GO terms for the gefitinib treatment group, YFSJ treatment group, and combination treatment group compared to the control group. Notably, the negative regulation of EMT showed significant enrichment in the DEGs of the combination treatment group. The MAPK pathway was significantly enriched among the different groups. Moreover, combined treatment with YFSJ and gefitinib may exert synergistic anti-NSCLC effects by inhibiting the p-p38 MAPK/GSK3β signalling axis, subsequently suppressing downstream EMT processes.

CONCLUSION

Combined treatment with YFSJ and gefitinib could enhance the sensitivity of NSCLC cells to gefitinib by suppressing EMT through the EGFR/p-p38 MAPK/GSK3β signalling axis. YFSJ may serve as an important adjunctive medication for NSCLC patients receiving gefitinib treatment in clinical practice.

Sinensetin inhibits the movement ability and tumor immune microenvironment of non-small cell lung cancer through the inactivation of AKT/β-catenin axis

Although current treatment strategies have improved clinical outcomes of non-small cell lung cancer (NSCLC) patients, side effect and prognosis remain a hindrance. Thus, safer and more effective therapeutical drugs are needed for NSCLC. Sinensetin (Sin) is a flavonoid from citrus fruits, which exhibits antitumor effect on diverse cancers. However, the effect and mechanism of Sin on NSCLC remain unknown. In this study, NSCLC cell lines, and tumor-bearing mice were treated with Sin. The effect and mechanism of Sin were addressed using cell counting kit-8, transwell, enzyme-linked immunosorbent assay, hematoxylin and eosin, immunohistochemistry, and western blot analysis assays in both cell and animal models. Sin reduced the cell viability of A549 and H1299, with the IC50 of 81.46 µM and 93.15 µM, respectively. Sin decreased invaded cell numbers, the expression of N-cadherin and vascular endothelial growth factor A (VEGFA), while increased the E-cadherin level, the cytotoxicity of CD8+ T cells, and the concentration of interferon-γ (IFN-γ), interleukin-2 (IL-2), and tumor necrosis factor-α (TNF-α) in NSCLC cells. Mechanistically, Sin declined the expression of protein kinase B (AKT)/β-catenin pathway, which was restored with the application of SC79, an activator of AKT. The inhibitory role of Sin in NSCLC cell proliferation, invasion, epithelial-mesenchymal transition (EMT) and immune escape was reversed by the management of SC79. In vivo, Sin reduced tumor size and weight, and the expression of N-cadherin, VEGFA, and AKT/β-catenin pathway, but enhanced the level of E-cadherin and IFN-γ. Taken together, Sin suppressed cell growth, invasion, EMT and immune escape via AKT/β-catenin pathway in NSCLC.

Snail transcription factors as key regulators of chemoresistance, stemness and metastasis of ovarian cancer cells

Ovarian cancer is one of the deadliest gynecological malignancies among women. The reason for this outcome is the frequent acquisition of cancer cell resistance to platinum-based drugs and unresponsiveness to standard therapy. It has been increasingly recognized that the ability of ovarian cancer cells to adopt more aggressive behavior (mainly through the epithelial-to-mesenchymal transition, EMT), as well as dedifferentiation into cancer stem cells, significantly affects drug resistance acquisition. Transcription factors in the Snail family have been implicated in ovarian cancer chemoresistance and metastasis. In this article, we summarize published data that reveal Snail proteins not only as key inducers of the EMT in ovarian cancer but also as crucial links between the acquisition of ovarian cancer stem properties and spheroid formation. These Snail-related characteristics significantly affect the ovarian cancer cell response to treatment and are related to the acquisition of chemoresistance.

Regulation of Tumor Apoptosis of Poriae cutis-Derived Lanostane Triterpenes by AKT/PI3K and MAPK Signaling Pathways In Vitro

Poria cocos is traditionally used as both food and medicine. Triterpenoids in Poria cocos have a wide range of pharmacological activities, such as diuretic, sedative and tonic properties. In this study, the anti-tumor activities of poricoic acid A (PAA) and poricoic acid B (PAB), purified by high-speed counter-current chromatography, as well as their mechanisms and signaling pathways, were investigated using a HepG2 cell model. After treatment with PAA and PAB on HepG2 cells, the apoptosis was obviously increased (p < 0.05), and the cell cycle arrested in the G2/M phase. Studies showed that PAA and PAB can also inhibit the occurrence and development of tumor cells by stimulating the generation of ROS in tumor cells and inhibiting tumor migration and invasion. Combined Polymerase Chain Reaction and computer simulation of molecular docking were employed to explore the mechanism of tumor proliferation inhibition by PAA and PAB. By interfering with phosphatidylinositol-3-kinase/protein kinase B, Mitogen-activated protein kinases and p53 signaling pathways; and further affecting the expression of downstream caspases; matrix metalloproteinase family, cyclin-dependent kinase -cyclin, Intercellular adhesion molecules-1, Vascular Cell Adhesion Molecule-1 and Cyclooxygenase -2, may be responsible for their anti-tumor activity. Overall, the results suggested that PAA and PAB induced apoptosis, halted the cell cycle, and inhibited tumor migration and invasion through multi-pathway interactions, which may serve as a potential therapeutic agent against cancer.

Combined PI3K Inhibitor and Eribulin Enhances Anti-Tumor Activity in Preclinical Models of Paclitaxel-Resistant, PIK3CA-Mutated Endometrial Cancer

Endometrial cancer stands as the predominant gynecological malignancy in developed nations. For advanced or recurrent disease, paclitaxel-based chemotherapy is the standard front-line therapy. However, paclitaxel resistance eternally develops. Based on the high prevalence of phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutation, reaching 50%, in endometrial cancer, we preclinically investigated the effectiveness of a combination of a phosphatidylinositol 3-kinase (PI3K) inhibitor with eribulin, a post-paclitaxel therapy for breast cancer, in treating paclitaxel-resistant, PIK3CA-mutated endometrial cancer. We generated paclitaxel-resistant cell lines from PIK3CA-mutated endometrial cancer cell lines by gradually increasing the concentration of paclitaxel in cell cultures. We observed that the PI3K/AKT and epithelial-mesenchymal transition (EMT) pathways in paclitaxel-resistant cells were significantly upregulated compared with those in parental cells. Then, we demonstrated that the combination of alpelisib (a PI3K inhibitor) and eribulin more effectively suppressed the cellular growth of paclitaxel-resistant cells in in vitro and in vivo xenograft models. Mechanistically, we demonstrated that the effect of the combination could be enhanced by inhibiting both the PI3K/AKT and EMT pathways. Therefore, we suggest that paclitaxel resistance is associated with the activation of the PIK3/AKT pathway in PIK3CA-mutated endometrial cancer, and the combination of a PI3K inhibitor and eribulin merits further clinical investigation.

Forkhead box proteins as the critical regulators of cisplatin response in tumor cells

Cisplatin (CDDP) is one of the most common chemotherapy drugs used in a wide range of cancer patients; however, there is a high rate of CDDP resistance among cancer patients. Considering the side effects of cisplatin in normal tissues, it is necessary to predict the CDDP response in cancer patients. Therefore, identifying the molecular mechanisms involved in CDDP resistance can help to introduce the prognostic markers. Several molecular mechanisms such as apoptosis inhibition, drug efflux, drug detoxification, and increased DNA repair are involved in CDDP resistance. Regarding the key role of transcription factors in regulation of many cellular processes related to drug resistance, in the present review, we discussed the role of Forkhead box (FOX) protein family in CDDP response. It has been reported that FOX proteins mainly promote CDDP resistance through the regulation of DNA repair, autophagy, epithelial-mesenchymal transition (EMT), and signaling pathways. Therefore, FOX proteins can be introduced as the prognostic markers to predict CDDP response in cancer patients. In addition, considering that oncogenic role of FOX proteins, the CDDP treatment along with FOX inhibition can be used as a therapeutic strategy in cancer patients.

Understanding and targeting resistance mechanisms in cancer

Resistance to cancer therapies has been a commonly observed phenomenon in clinical practice, which is one of the major causes of treatment failure and poor patient survival. The reduced responsiveness of cancer cells is a multifaceted phenomenon that can arise from genetic, epigenetic, and microenvironmental factors. Various mechanisms have been discovered and extensively studied, including drug inactivation, reduced intracellular drug accumulation by reduced uptake or increased efflux, drug target alteration, activation of compensatory pathways for cell survival, regulation of DNA repair and cell death, tumor plasticity, and the regulation from tumor microenvironments (TMEs). To overcome cancer resistance, a variety of strategies have been proposed, which are designed to enhance the effectiveness of cancer treatment or reduce drug resistance. These include identifying biomarkers that can predict drug response and resistance, identifying new targets, developing new targeted drugs, combination therapies targeting multiple signaling pathways, and modulating the TME. The present article focuses on the different mechanisms of drug resistance in cancer and the corresponding tackling approaches with recent updates. Perspectives on polytherapy targeting multiple resistance mechanisms, novel nanoparticle delivery systems, and advanced drug design tools for overcoming resistance are also reviewed.

Cytotoxic Effects of Nanoliposomal Cisplatin and Diallyl Disulfide on Breast Cancer and Lung Cancer Cell Lines

Dual drug delivery has become the choice of interest nowadays due to its increased therapeutic efficacy in targeting the tumor site precisely. As quoted in recent literature, it has been known to treat several cancers with an acute course of action. Even so, its use is restricted due to the drug’s low pharmacological activity, which leads to poor bioavailability and increases first-pass metabolism. To overcome these issues, a drug delivery system using nanomaterials which would not only encapsulate the drugs of interest but also carry them to the target site of action is needed. Given all these attributes, we have formulated dual drug-loaded nanoliposomes with cisplatin (cis-diamminedichloroplatinum(II) (CDDP)), an effective anti-cancer drug, and diallyl disulfide (DADS), an organosulfur compound derived from garlic. The CDDP and DADS-loaded nanoliposomes (Lipo-CDDP/DADS) exhibited better physical characteristics such as size, zeta potential, polydispersity index, spherical shape, optimal stability, and satisfactory encapsulation percentage. The in vitro anti-cancer activity against MDA-MB-231 and A549 cell lines revealed that Lipo-CDDP/DADS showed significant efficacy against the cancer cell lines, depicted through cell nucleus staining. We conclude that Lipo-CDDP/DADS hold exceptional pharmacological properties with better anti-cancer activity and would serve as a promising formulation to treat various cancers.

Hypoxia, but Not Normoxia, Reduces Effects of Resveratrol on Cisplatin Treatment in A2780 Ovarian Cancer Cells: A Challenge for Resveratrol Use in Anticancer Adjuvant Cisplatin Therapy

Natural compounds, such as resveratrol (Res), are currently used as adjuvants for anticancer therapies. To evaluate the effectiveness of Res for the treatment of ovarian cancer (OC), we screened the response of various OC cell lines to the combined treatment with cisplatin (CisPt) and Res. We identified A2780 cells as the most synergistically responding, thus optimal for further analysis. Because hypoxia is the hallmark of the solid tumor microenvironment, we compared the effects of Res alone and in combination with CisPt in hypoxia (pO2 = 1%) vs. normoxia (pO2 = 19%). Hypoxia caused an increase (43.2 vs. 5.0%) in apoptosis and necrosis (14.2 vs. 2.5%), reactive oxygen species production, pro-angiogenic HIF-1α (hypoxia-inducible factor-1α) and VEGF (vascular endothelial growth factor), cell migration, and downregulated the expression of ZO1 (zonula occludens-1) protein in comparison to normoxia. Res was not cytotoxic under hypoxia in contrast to normoxia. In normoxia, Res alone or CisPt+Res caused apoptosis via caspase-3 cleavage and BAX, while in hypoxia, it reduced the accumulation of A2780 cells in the G2/M phase. CisPt+Res increased levels of vimentin under normoxia and upregulated SNAI1 expression under hypoxia. Thus, various effects of Res or CisPt+Res on A2780 cells observed in normoxia are eliminated or diminished in hypoxia. These findings indicate the limitations in using Res as an adjuvant with CisPt therapy in OC.

A deep tabular data learning model predicting cisplatin sensitivity identifies BCL2L1 dependency in cancer

Cisplatin, a platinum-based chemotherapeutic agent, is widely used as a front-line treatment for several malignancies. However, treatment outcomes vary widely due to intrinsic and acquired resistance. In this study, cisplatin-perturbed gene expression and pathway enrichment were used to define a gene signature, which was further utilized to develop a cisplatin sensitivity prediction model using the TabNet algorithm. The TabNet model performed better (>80 % accuracy) than all other machine learning models when compared to a wide range of machine learning algorithms. Moreover, by using feature importance and comparing predicted ovarian cancer patient samples, BCL2L1 was identified as an important gene contributing to cisplatin resistance. Furthermore, the pharmacological inhibition of BCL2L1 was found to synergistically increase cisplatin efficacy. Collectively, this study developed a tool to predict cisplatin sensitivity using cisplatin-perturbed gene expression and pathway enrichment knowledge and identified BCL2L1 as an important gene in this setting.

Wnt/β-Catenin Signaling and Resistance to Immune Checkpoint Inhibitors: From Non-Small-Cell Lung Cancer to Other Cancers

Lung cancer is the leading cause of cancer-related deaths worldwide. The standard of care for advanced non-small-cell lung cancer (NSCLC) without driver-gene mutations is a combination of an anti-PD-1/PD-L1 antibody and chemotherapy, or an anti-PD-1/PD-L1 antibody and an anti-CTLA-4 antibody with or without chemotherapy. Although there were fewer cases of disease progression in the early stages of combination treatment than with anti-PD-1/PD-L1 antibodies alone, only approximately half of the patients had a long-term response. Therefore, it is necessary to elucidate the mechanisms of resistance to immune checkpoint inhibitors. Recent reports of such mechanisms include reduced cancer-cell immunogenicity, loss of major histocompatibility complex, dysfunctional tumor-intrinsic interferon-γ signaling, and oncogenic signaling leading to immunoediting. Among these, the Wnt/β-catenin pathway is a notable potential mechanism of immune escape and resistance to immune checkpoint inhibitors. In this review, we will summarize findings on these resistance mechanisms in NSCLC and other cancers, focusing on Wnt/β-catenin signaling. First, we will review the molecular biology of Wnt/β-catenin signaling, then discuss how it can induce immunoediting and resistance to immune checkpoint inhibitors. We will also describe other various mechanisms of immune-checkpoint-inhibitor resistance. Finally, we will propose therapeutic approaches to overcome these mechanisms.

Ferroptosis as a Potential Cell Death Mechanism Against Cisplatin-Resistant Lung Cancer Cell Line

Purpose: Drug resistance is a challenging issue in cancer chemotherapy. Cell death induction is one of the main strategies to overcome chemotherapy resistance. Notably, ferroptosis has been considered a critical cell death mechanism in recent years. Accordingly, in this study, the different cell death strategies focused on ferroptosis have been utilized to overcome cisplatin resistance in an in vitro lung cancer model. Methods: The physiological functions of Akt1 and GPX4, as critical targets for ferroptosis and apoptosis induction, were suppressed by siRNA or antagonistic agents in resistant A549 cells. Afterward, the interventions' impacts on cell viability and reactive oxygen species (ROS) amount were analyzed by flow cytometry. Moreover, the alteration in the relevant gene and protein expression levels were quantified using Real-time PCR and western blot methods. Results: The result showed that the treatment with Akt1 siRNA reversed the cisplatin resistance in the A549 cell line through the induction of apoptosis. Likewise, the combination treatment of the GPX4 siRNA or FIN56 as ferroptosis inducers alongside cisplatin elevated ROS's cellular level, reduced the cellular antioxidant genes level and increased the cisplatin cytotoxic effect. Conclusion: In conclusion, our study indicated that ferroptosis induction can be considered a promising cell death strategy in cisplatin-resistant cancer cells.

COM33 suppresses carboplatin-induced epithelial-mesenchymal transition via inhibition of Twist1 in ovarian cancer

Despite favorable responses to platinum-based chemotherapy in ovarian cancer (OC), chemoresistance is still a major cause of treatment failure. Hence, we develop a novel synthetic agent, COM33, to relieve the chemoresistance caused by carboplatin. The anti-cancerous effects of the combination of COM33 and carboplatin on OC are evaluated by cell viability, wound healing, and transwell invasion assays. A mechanistic investigation is carried out by using RNA-Seq analysis and then verified by western blot analysis and immunofluorescence microscopy. The safety and efficacy in vivo are evaluated using SKOV3 tumor-bearing nude mice. Results show that the co-administration of COM33 enhances the inhibitory effects of carboplatin on cancer cell viability, migration, and invasion in vitro and tumor growth in vivo. Furthermore, COM33 suppresses the carboplatin-induced epithelial-mesenchymal transition (EMT) by inhibiting the ERK signaling pathway. Additionally, we show that Twist1, the effector of the ERK signaling pathway, participates in carboplatin-induced EMT and is also inhibited by COM33. Our data show that the combination of carboplatin with COM33 is beneficial for chemotherapy against OC, which may be a potential novel anti-tumor strategy.

HIV-1 Proteins gp120 and Tat Promote Epithelial-Mesenchymal Transition and Invasiveness of HPV-Positive and HPV-Negative Neoplastic Genital and Oral Epithelial Cells

The incidence of human papillomavirus (HPV)-associated anogenital and oropharyngeal cancer in human immunodeficiency virus (HIV)-infected individuals is substantially higher than in HIV-uninfected individuals. HIV may also be a risk factor for the development of HPV-negative head and neck, liver, lung, and kidney cancer. However, the molecular mechanisms underlying HIV-1-associated increase of epithelial malignancies are not fully understood. Here, we showed that HPV-16-immortalized anal AKC-2 and cervical CaSki epithelial cells that undergo prolonged exposure to cell-free HIV-1 virions or HIV-1 viral proteins gp120 and tat respond with the epithelial-mesenchymal transition (EMT) and increased invasiveness. Similar responses were observed in HPV-16-infected SCC-47 and HPV-16-negative HSC-3 oral epithelial cancer cells that were cultured with these viral proteins. EMT induced by gp120 and tat led to detachment of poorly adherent cells from the culture substratum; these cells remained capable of reattachment, upon which they coexpressed both E-cadherin and vimentin, indicative of an intermediate stage of EMT. The reattached cells also expressed stem cell markers CD133 and CD44, which may play a critical role in cancer cell invasion and metastasis. Inhibition of transforming growth factor (TGF)-β1 and MAPK signaling and vimentin expression, and restoration of E-cadherin expression reduced HIV-induced EMT and the invasive activity of HPV-16-immortalized anal and cervical epithelial cells. Collectively, our results suggest that these approaches along with HIV viral suppression with antiretroviral therapy (ART) might be useful to limit the role of HIV-1 infection in the acceleration of HPV-associated or HPV-independent epithelial neoplasia. IMPORTANCE HPV-16-immortalized genital and oral epithelial cells and HPV-negative oral cancer cells that undergo prolonged contact with cell-free HIV-1 virions or with viral proteins gp120 and tat respond by becoming more invasive. EMT cells induced by HIV-1 in cultures of HPV-16-immortalized anal and cervical epithelial cells express the stem cell markers CD133 and CD44. These results suggest that the interaction of HIV-1 with neoplastic epithelial cells may lead to their de-differentiation into cancer stem cells that are resistant to apoptosis and anti-cancer drugs. Thus, this pathway may play a critical role in the development of invasive cancer. Inhibition of TGF-β1 and MAPK signaling and vimentin expression, and restoration of E-cadherin expression reduced HIV-induced EMT and the invasiveness of HPV-16-immortalized anal and cervical epithelial cells. Taken together, these results suggest that these approaches might be exploited to limit the role of HIV-1 infection in the acceleration of HPV-associated or HPV-independent epithelial neoplasia.

Down-regulation of hepatic expression of GHR/STAT5/IGF-1 signaling pathway fosters development and aggressiveness of HCV-related hepatocellular carcinoma: Crosstalk with Snail-1 and type 2 transforming growth factor-beta receptor

Background and aims

So far, few clinical trials are available concerning the role of growth hormone receptor (GHR)/signal transducer and activator of transcription 5 (STAT5)/insulin like growth factor-1 (IGF-1) axis in hepatocarcinogenesis. The aim of this study was to evaluate the hepatic expression of GHR/STAT5/IGF-1 signaling pathway in hepatocellular carcinoma (HCC) patients and to correlate the results with the clinico-pathological features and disease outcome. The interaction between this signaling pathway and some inducers of epithelial-mesenchymal transition (EMT), namely Snail-1 and type 2 transforming growth factor-beta receptor (TGFBR2) was studied too.

Material and methods

A total of 40 patients with HCV-associated HCC were included in this study. They were compared to 40 patients with HCV-related cirrhosis without HCC, and 20 healthy controls. The hepatic expression of GHR, STAT5, IGF-1, Snail-1 and TGFBR2 proteins were assessed by immunohistochemistry.

Results

Compared with cirrhotic patients without HCC and healthy controls, cirrhotic patients with HCC had significantly lower hepatic expression of GHR, STAT5, and IGF-1proteins. They also displayed significantly lower hepatic expression of TGFBR2, but higher expression of Snail-1 versus the non-HCC cirrhotic patients and controls. Serum levels of alpha-fetoprotein (AFP) showed significant negative correlations with hepatic expression of GHR (r = -0.31; p = 0.029) and STAT5 (r = -0.29; p = 0.04). Hepatic expression of Snail-1 also showed negative correlations with GHR, STAT5, and IGF-1 expression (r = -0.55, p = 0.02; r = -0.472, p = 0.035, and r = -0.51, p = 0.009, respectively), whereas, hepatic expression of TGFBR2 was correlated positively with the expression of all these proteins (r = 0.47, p = 0.034; 0.49, p = 0.023, and r = 0.57, p<0.001, respectively). Moreover, we reported that decreased expression of GHR was significantly associated with serum AFP level>100 ng/ml (p = 0.048), increased tumor size (p = 0.02), vascular invasion (p = 0.002), and advanced pathological stage (p = 0.01). Similar significant associations were found between down-regulation of STAT5 expression and AFP level > 100 ng/ml (p = 0.006), vascular invasion (p = 0.009), and advanced tumor stage (p = 0.007). Also, attenuated expression of IGF-1 showed a significant association with vascular invasion (p < 0.001). Intriguingly, we detected that lower expression of GHR, STAT5 and IGF-1 were considered independent predictors for worse outcome in HCC.

Conclusion

Decreased expression of GHR/STAT5/IGF-1 signaling pathway may have a role in development, aggressiveness, and worse outcome of HCV-associated HCC irrespective of the liver functional status. Snail-1 and TGFBR2 as inducers of EMT may be key players. However, large prospective multicenter studies are needed to validate these results.

Selenium Yeast and Fish Oil Combination Diminishes Cancer Stem Cell Traits and Reverses Cisplatin Resistance in A549 Sphere Cells

Cisplatin is a prevalent chemotherapeutic agent used for non-small cell lung cancer (NSCLC) that is difficult to treat by targeted therapy, but the emergence of resistance severely limits its efficacy. Thus, an effective strategy to combat cisplatin resistance is required. This study demonstrated that, at clinically achievable concentrations, the combination of selenium yeast (Se-Y) and fish oil (FO) could synergistically induce the apoptosis of cancer stem cell (CSC)-like A549 NSCLC sphere cells, accompanied by a reversal of their resistance to cisplatin. Compared to parental A549 cells, sphere cells have higher cisplatin resistance and possess elevated CSC markers (CD133 and ABCG2), epithelial-mesenchymal transition markers (anexelekto (AXL), vimentin, and N-cadherin), and cytoprotective endoplasmic reticulum (ER) stress marker (glucose-regulated protein 78) and increased oncogenic drivers, such as yes-associated protein, transcriptional coactivator with PDZ-binding motif, β-catenin, and cyclooxygenase-2. In contrast, the proapoptotic ER stress marker CCAAT/enhancer-binding protein homologous protein and AMP-activated protein kinase (AMPK) activity were reduced in sphere cells. The Se-Y and FO combination synergistically counteracted the above molecular features of A549 sphere cells and diminished their elevated CSC-like side population. AMPK inhibition by compound C restored the side population proportion diminished by this nutrient combination. The results suggest that the Se-Y and FO combination can potentially improve the outcome of cisplatin-treated NSCLC with phenotypes such as A549 cells.

CNTN-1 Upregulation Induced by Low-Dose Cisplatin Promotes Malignant Progression of Lung Adenocarcinoma Cells via Activation of Epithelial-Mesenchymal Transition

Tumor metastasis and invasion are the main impediments to lung adenocarcinoma successful treatment. Previous studies demonstrate that chemotherapeutic agents can elevate the malignancy of cancer cells other than their therapeutic effects. In this study, the effects of transient low-dose cisplatin treatment on the malignant development of lung adenocarcinoma cells (A549) were detected, and the underlying epigenetic mechanisms were investigated. The findings showed that A549 cells exhibited epithelial-mesenchymal transition (EMT)-like phenotype along with malignant progression under the transient low-dose cisplatin treatment. Meanwhile, low-dose cisplatin was found to induce contactin-1 (CNTN-1) upregulation in A549 cells. Subsequently, we found that further overexpressing CNTN-1 in A549 cells obviously activated the EMT process in vitro and in vivo, and caused malignant development of A549 cells in vitro. Taken together, we conclude that low-dose cisplatin can activate the EMT process and resulting malignant progression through upregulating CNTN-1 in A549 cells. The findings provided new evidence that a low concentration of chemotherapeutic agents could facilitate the malignancy of carcinoma cells via activating the EMT process other than their therapeutic effects.

Transcriptomics reveals in vivo efficacy of PARP inhibitor combinatorial synergy with platinum-based chemotherapy in human non-small cell lung carcinoma models

Inhibitors of poly(ADP)-ribose polymerase (PARP) exploit defective DNA repair pathways existing in several forms of cancer, such as those with BRCA mutations, and have proven clinical efficacy as chemosensitizers. However, platinum-based chemopotentiation by PARP inhibitors (PARPi), particularly for non-small cell lung cancer (NSCLC), has only been confirmed in a few preclinical models and the molecular mechanisms that drive PARPi combinatorial synergy with chemotherapeutics remains poorly defined. To better understand these mechanisms, we characterized cisplatin and veliparib efficacy in A549 and Calu6 NSCLC in vivo tumor xenograft models and observed combinatorial synergy in the Calu6 model. Transcriptome-wide analysis of xenografts revealed several differentially expressed genes (DEGs) between untreated and cisplatin + veliparib-treated groups, which were unique from genes identified in either of the single-agent treatment arms. Particularly at 10- and 21-days post-treatment, these DEGs were enriched within pathways involved in DNA damage repair, cell cycle regulation, and senescence. Furthermore, TGF-β- and integrin-related pathways were enriched in the combination treatment arm, while pathways involved in cholesterol metabolism were identified at earlier time points in both the combination and cisplatin-only groups. These data advance the biological underpinnings of PARPi combined with platinum-based chemotherapy and provides additional insight into the diverse sensitivity of NSCLC models.

Impact of Cancer Stem Cells and Cancer Stem Cell-Driven Drug Resiliency in Lung Tumor: Options in Sight

Causing a high mortality rate worldwide, lung cancer remains an incurable malignancy resistant to conventional therapy. Despite the discovery of specific molecular targets and new treatment strategies, there remains a pressing need to develop more efficient therapy to further improve the management of this disease. Cancer stem cells (CSCs) are considered the root of sustained tumor growth. This consensus corroborates the CSC model asserting that a distinct subpopulation of malignant cells within a tumor drives and maintains tumor progression with high heterogeneity. Besides being highly tumorigenic, CSCs are highly refractory to standard drugs; therefore, cancer treatment should be focused on eliminating these cells. Herein, we present the current knowledge of the existence of CSCs, CSC-associated mechanisms of chemoresistance, the ability of CSCs to evade immune surveillance, and potential CSC inhibitors in lung cancer, to provide a wider insight to drive a more efficient elimination of this pro-oncogenic and treatment-resistant cell fraction.

TRIM55 suppresses malignant biological behavior of lung adenocarcinoma cells by increasing protein degradation of Snail1

Up until now, cancer refractoriness and distal organ metastatic disease remain as major obstacles for oncologists to achieve satisfactory therapeutic effects for lung adenocarcinoma patients. Previous studies indicated that TRIM55, which participates in the natural development of muscle and cardiovascular system, plays a protective role in hepatocellular carcinoma (HCC) pathogenesis. Therefore, in this study, we aimed to unveil the detailed molecular mechanism of TRIM55 and identify the potential target for lung adenocarcinoma patients. Surgical samples and lung cancer cell lines were collected to detect the TRIM55 expression for patients with or without lymph node/distal organ metastasis. Cellular functional assays including transwell assay, wound healing assay, cellular survivability assay, etc. as well as ubiquitination assay were performed to evaluate the impact of TRIM55/Snail1 regulatory network via the UPP pathway on lung cancer tumor cell migration and chemo-resistance. Lung cancer tissues and tumor cell lines exhibited significantly lower levels of TRIM55 expression. Functional study further indicated that TRIM55 inhibited chemo-resistance, migration, and cancer stem-cell like phenotype of tumor cells. Further detailed molecular experiments indicated that TRIM55 promoted degradation of Snail1 via the UPP pathway, which played an interesting role in the regulation of cancer cell malignancy. This study provided novel theory that TRIM55 acted as a potential tumor suppressor by inhibition of tumor cell malignancy through enhancement of Snail1 degradation via the UPP pathway. Our research will inspire further exploration on TRIM55 to promote therapeutic effects for lung adenocarcinoma patients.

Melatonin and its derivative disrupt cancer stem-like phenotypes of lung cancer cells via AKT downregulation

Cancer stem cells (CSCs), a small subpopulation of tumour cells, have properties of self-renewal and multipotency, which drive cancer progression and resistance to current treatments. Compounds potentially targeting CSCs have been recently developed. This study shows how melatonin, an endogenous hormone synthesised by the pineal gland, and its derivative suppress CSC-like phenotypes of human non-small cell lung cancer (NSCLC) cell lines, H460, H23, and A549. The effects of MLT and its derivative, acetyl melatonin (ACT), on CSC-like phenotypes were investigated using assays for anchorage-independent growth, three-dimensional spheroid formation, scratch wound healing ability, and CSC marker and upstream protein signalling expression. Enriched CSC spheroids were used to confirm the effect of both compounds on lung cancer cells. MLT and ACT inhibited CSC-like behaviours by suppression of colony and spheroid formation in NSCLC cell lines. Their effects on spheroid formation were confirmed in CSC-enriched H460 cells. CSC markers, CD133 and ALDH1A1, were depleted by both compounds. The behaviour and factors associated to epithelial-mesenchymal transition, as indicated by cell migration and the protein vimentin, were also decreased by MLT and ACT. Mechanistically, MLT and ACT decreased the expression of stemness proteins Oct-4, Nanog, and β-catenin by reducing active AKT (phosphorylated AKT). Suppression of the AKT pathway was not mediated through melatonin receptors. This study demonstrates a novel role, and its underlying mechanism, for MLT and its derivative ACT in suppression of CSC-like phenotypes in NSCLC cells, indicating that they are potential candidates for lung cancer treatment.

Survival Outcome and Clinicopathologicl analysis of Homeobox gene cluster-embedded LncRNAs in Human Cancers: A Systematic Review and Meta-analysis

OBJECTIVE

The ectopic expression of Homeobox (HOX) gene cluster-embedded long non-coding RNAs (LncRNAs) have been involved several carcinogenic development and progressions. This meta-analysis aimed to summarize the LncRNAs to validate the functions and the prognostic values in several kinds of cancer.

METHODS

The retrospective study was conducted to analyze the association between HOX gene-related LncRNAs and the survival outcomes. Cochran's Q and I² test were used for calculated heterogeneity, and I² > 50%, P < 0.05 was conformed to the random effect model. Publication bias was indicated by Begg's and Egger's test.

RESULTS

Total 15,315 patients extracting from 121 studies focused on assessing the association between LncRNAs and the survival outcomes and 12,110 participants were enrolled to address the clinicopathological features. The results demonstrated that the overexpression of HOX gene cluster-embedded LncRNAs revealed notable association among tumor size (pooled OR = 1.80), lymph node metastasis (LNM) stage (pooled OR = 3.00), tumor node metastasis (TNM) stage (pooled OR = 2.86), histological differentiation (pooled OR = 1.59) and distant metastasis (pooled OR = 2.49). Additionally, the up-regulated LncRNAs predicted a poor prognosis in overall survival (pooled HR = 1.95, 95%CI = 1.86-2.04), and also disclosed worse prognosis among the stratified analysis included HOX clusters, LncRNAs, ethnicity, and tumor classification (pooled HRs >1).

CONCLUSION

In summary, the findings proved that HOX gene cluster-embedded LncRNAs acted as potential biomarkers for clinical treatment of several tumors and the overexpression might be a candidate hallmark for prognosis outcome.

MicroRNA‑10b modulates cisplatin tolerance by targeting p53 directly in lung cancer cells

MicroRNA (miRNA or miR)‑10b is an oncogenic miRNA associated with metastasis that is present in various types of tumor, including lung cancer. However, whether miR‑10b is involved in different malignant characteristics, such as drug resistance or stemness, remains unclear. Therefore, the present study investigated whether miR‑10b is an upstream regulator of p53. Ectopic expression of miR‑10b‑agomir decreased the expression of p53 and its downstream effectors, such as Bax and p53 upregulated modulator of apoptosis. Two non‑canonical sites, including 1,580‑1,587 and 2,029‑2,035, located in p53 3'‑untranslated region (UTR) were affected by the presence of miR‑10b. In functional assays, upregulation of the p53 signaling pathway following cisplatin treatment was associated with decreased levels of miR‑10b and upregulation of the luciferase activity of wild‑type, but not 1,584, 2,032‑dual‑mutant, p53 3'‑UTR. The ectopic expression of miR‑10b‑agomir attenuated the stability of p53 3'‑UTR and the expression of p53 and its downstream effectors induced by cisplatin. By contrast, the knockdown of miR‑10b induced the stability of p53 3'‑UTR and increased levels of p53 and the sensitivity of A549 cells to cisplatin treatment. Similar results were also observed for Beas 2B cells. In the clinical investigation, p53 exhibited two distinct associations (cocurrent and countercurrent) with miR‑10b in patients with lung cancer. Patients with lung cancer with low p53 and high miR‑10b levels exhibited the poorest prognosis, while those with high p53 and low miR‑10b exhibited the most favorable prognosis. These findings indicate a novel pathway in which cisplatin induces the levels of p53 by increasing mRNA stability via miR‑10b, indicating a novel oncogenic role of miR‑10b in promoting the malignant characteristics of non‑small cell lung carcinoma.

PER2-mediated ameloblast differentiation via PPARγ/AKT1/β-catenin axis

Circadian rhythm is involved in the development and diseases of many tissues. However, as an essential environmental regulating factor, its effect on amelogenesis has not been fully elucidated. The present study aims to investigate the correlation between circadian rhythm and ameloblast differentiation and to explore the mechanism by which circadian genes regulate ameloblast differentiation. Circadian disruption models were constructed in mice for in vivo experiments. An ameloblast-lineage cell (ALC) line was used for in vitro studies. As essential molecules of the circadian system, Bmal1 and Per2 exhibited circadian expression in ALCs. Circadian disruption mice showed reduced amelogenin (AMELX) expression and enamel matrix secretion and downregulated expression of BMAL1, PER2, PPARγ, phosphorylated AKT1 and β-catenin, cytokeratin-14 and F-actin in ameloblasts. According to previous findings and our study, BMAL1 positively regulated PER2. Therefore, the present study focused on PER2-mediated ameloblast differentiation and enamel formation. Per2 knockdown decreased the expression of AMELX, PPARγ, phosphorylated AKT1 and β-catenin, promoted nuclear β-catenin accumulation, inhibited mineralization and altered the subcellular localization of E-cadherin in ALCs. Overexpression of PPARγ partially reversed the above results in Per2-knockdown ALCs. Furthermore, in in vivo experiments, the length of incisor eruption was significantly decreased in the circadian disturbance group compared to that in the control group, which was rescued by using a PPARγ agonist in circadian disturbance mice. In conclusion, through regulation of the PPARγ/AKT1/β-catenin signalling axis, PER2 played roles in amelogenin expression, cell junctions and arrangement, enamel matrix secretion and mineralization during ameloblast differentiation, which exert effects on enamel formation.

Differential effects of cisplatin combined with the flavonoid apigenin on HepG2, Hep3B, and Huh7 liver cancer cell lines

The potential of apigenin (APG) to enhance cisplatin's (CDDP) chemotherapeutic efficacy was investigated in HepG2, Hep3B, and Huh7 liver cancer cell lines. The presence of 20 μM APG sensitized all cell lines to CDDP treatment (degree of sensitization based on the MTT assay: HepG2>Huh7>Hep3B). As reflected by sister chromatid exchange levels, the degree of genetic instability as well as DNA repair by homologous recombination differed among cell lines. CDDP and 20 μM APG cotreatment exhibited a synergistic genotoxic effect on Hep3B cells and a less than additive effect on HepG2 and Huh7 cells. Cell cycle delays were noticed during the first mitotic division in Hep3B and Huh7 cells and the second mitotic division in HepG2 cells. CDDP and CDDP + APG treatments reduced the clonogenic capacity of all cell lines; however, there was a discordance in drug sensitivity compared with the MMT assay. Furthermore, a senescence-like phenotype was induced, especially in Hep3B and Huh7 cells. Unlike CDDP monotherapy, the combined treatment exhibited a significant anti-invasive and anti-migratory action in all cancer cell lines. The fact that the three liver cancer cell lines responded differently, yet positively, to CDDP + APG cotreatment could be attributed to variations they present in gene expression. Complex mechanisms seem to influence cellular responses and cell fate.

MicroRNA-506-3p increases the response to PARP inhibitors and cisplatin by targeting EZH2/β-catenin in serous ovarian cancers

Chemo-resistance is an important barrier to effective treatment of ovarian cancer. Poly (ADP-ribose) polymerase (PARP) inhibitors are currently promising targeted drugs used to treat BRCA-mutant ovarian cancer. Ovarian cancer patients with BRCA 1/2 mutations appear to benefit better from PARP inhibitors and chemotherapy. Understanding the mechanisms underlying PARP inhibitors and chemotherapy resistance is urgently needed. There is increasing evidence that microRNAs (miRNAs) are involved in drug resistance. MiR-506-3p is an effective inhibitor of the epithelial-to-mesenchymal transition (EMT), and can enhance chemotherapy and olaparib response in high-grade serous ovarian cancer (HGS-OvCa). Enhancer of Zeste Homolog 2 (EZH2) is considered as a direct target of miR-506-3p. The silencing of EZH2 mimics the inhibitory effects of miR-506-3p on chemo-resistance and olaparib response. Rescue of EZH2 prevented the functions of miR-506-3p. Moreover, EZH2 activates the β-catenin pathway. MiR-506-3p overexpression decreased the level of β-catenin, and the sensitivity to olaparib and cisplatin mediated by miR-506-3p was partially reversed by regulating β-catenin expression in ovarian cancer. Our results suggest that miR-506-3p increases response to PARP inhibitors and cisplatin in serous ovarian cancer by targeting EZH2/β-catenin signal pathway, which opens the possibility of using miR-506-3p overexpression as a potential therapeutic for ovarian cancer.

Tumor β-catenin expression is associated with immune evasion in non-small cell lung cancer with high tumor mutation burden

β-catenin expression by tumor cells suppressed dendritic cell recruitment to the tumor microenvironment in a melanoma model, resulting in fewer tumor-infiltrating lymphocytes. Immunohistochemistry was used in the present study to examine the association between the expression of β-catenin and tumor infiltrating lymphocytes and CD11c⁺ cells in 122 patients with non-small cell lung cancer (NSCLC), who underwent radical surgery. β-catenin was positive in 24% of NSCLC tumors compared with 59% of squamous cell carcinomas and 11% of adenocarcinomas. There was no significant association between the expression of β-catenin and the frequency of CD8⁺ cell infiltration into tumor tissues, including the stroma. Conversely, the infiltration of CD8⁺ cells into tumor nests was significantly lower in β-catenin-positive cases compared with that in negative β-catenin cases. Similarly, CD11c⁺ cell infiltration was significantly lower in the β-catenin-positive group. The β-catenin-positive group had shorter overall survival and recurrence-free survival times compared with that in the negative group. Furthermore, β-catenin-positive NSCLC had a high tumor mutation burden, but tended to have a low expression of programmed death-ligand 1. In conclusion, the expression of β-catenin in NSCLC was negatively associated with CD11c⁺ cells and cytotoxic T cell infiltration at the tumor site and had a tendency towards a poor prognosis.

Atmospheric fine particulate matter and epithelial mesenchymal transition in pulmonary cells: state of the art and critical review of the in vitro studies

Exposure to fine particulate matter (PM_2.5) has been associated with several diseases including asthma, chronic obstructive pulmonary disease (COPD) and lung cancer. Mechanisms such as oxidative stress and inflammation are well-documented and are considered as the starting point of some of the pathological responses. However, a number of studies also focused on epithelial-mesenchymal transition (EMT), which is a biological process involved in fibrotic diseases and cancer progression notably via metastasis induction. Up until now, EMT was widely reported in vivo and in vitro in various cell types but investigations dealing with in vitro studies of PM_2.5 induced EMT in pulmonary cells are limited. Further, few investigations combined the necessary endpoints for validation of the EMT state in cells: such as expression of several surface, cytoskeleton or extracellular matrix biomarkers and activation of transcription markers and epigenetic factors. Studies explored various cell types, cultured under differing conditions and exposed for various durations to different doses. Such unharmonized protocols (1) might introduce bias, (2) make difficult comparison of results and (3) preclude reaching a definitive conclusion regarding the ability of airborne PM_2.5 to induce EMT in pulmonary cells. Some questions remain, in particular the specific PM_2.5 components responsible for EMT triggering. The aim of this review is to examine the available PM_2.5 induced EMT in vitro studies on pulmonary cells with special emphasis on the critical parameters considered to carry out future research in this field. This clarification appears necessary for production of reliable and comparable results.

The AKT/GSK3-Mediated Slug Expression Contributes to Oxaliplatin Resistance in Colorectal Cancer via Upregulation of ERCC1

Although oxaliplatin serves as one of the first-line drugs prescribed for treating colorectal cancer (CRC), the therapeutic effect is disappointing due to drug resistance. So far, the molecular mechanisms mediating oxaliplatin resistance remain unclear. In this study, we found the chemoresistance in oxaliplatin-resistant HCT116 cells (HCT116/OXA) was mediated by the upregulation of ERCC1 expression. In addition, the acquisition of resistance induced epithelialmesenchymal transition (EMT) as well as the Slug overexpression. On the contrary, Slug silencing reversed the EMT phenotype, decreased ERCC1 expression, and ameliorated drug resistance. Further mechanistical studies revealed the enhanced Slug expression resulted from the activation of AKT/glycogen synthase kinase 3 (GSK3) signaling. Moreover, in CRC patients, coexpression of Slug and ERCC1 was observed, and increased Slug expression was significantly correlated with clinicopathological factors and prognosis. Taken together, the simultaneous inhibition of the AKT/GSK3/Slug axis may be of significance for surmounting metastasis and chemoresistance, thereby improving the therapeutic outcome of oxaliplatin.

Soluble (pro)renin receptor promotes the fibrotic response in renal proximal tubule epithelial cells in vitro via the Akt/β-catenin/Snail signaling pathway

Tubulointerstitial fibrosis has been regarded as a critical event in the pathogenesis of chronic kidney disease. The soluble form of (pro)renin receptor (sPRR), generated by site-1 protease (S1P) cleavage of full-length PRR, can be detected in biological fluid and elevated under certain pathological conditions. The present study was designed to evaluate the potential role of sPRR in the regulation of the fibrotic response in a cultured human renal proximal tubular cell line (HK-2 cells) in the setting of transforming growth factor (TGF)-β or sPRR-His treatment. The TGF-β-induced fibrotic response of HK-2 cells was indicated by upregulation of fibronectin (FN) expression; meanwhile, TGF-β could also induce the generation of sPRR, due to enhanced cleavage of full-length PRR. To explore the role of sPRR in the fibrotic response of HK-2 cells, we blocked the production of sPRR with a the S1P inhibitor PF429242 and found that PF429242 remarkably suppressed TGF-β-induced sPRR generation and FN expression in HK-2 cells. Administration of sPRR-His restored the PF429242-attenuated FN expression in HK-2 cells, indicating that sPRR could promote the TGF-β-induced fibrotic response. Furthermore, sPRR-His alone also increased the abundance of FN in HK-2 cells. These data suggested that sPRR was sufficient and necessary for the TGF-β-induced fibrotic response of HK-2 cells. Mechanistically, sPRR activated the AKT and β-catenin pathway in HK-2 cells, and blockade of the AKT or β-catenin pathway significantly abrogated sPRR-induced FN and Snail expression. Taking together, sPRR promoted the fibrotic response of HK-2 cells by activating Akt/β-catenin/Snail signaling, and it may serve as a potential therapeutic target in renal fibrosis.

Reelin Promotes Cisplatin Resistance by Induction of Epithelial-Mesenchymal Transition via p38/GSK3β/Snail Signaling in Non-Small Cell Lung Cancer

Background

Emerging evidence suggests the involvement of Reelin in chemoresistance in various cancers. However, its function in cisplatin (DDP) sensitivity of non-small cell lung cancer (NSCLC) needs to be investigated.

Material/Methods

Reelin expression in cisplatin-sensitive A549 cells and cisplatin-resistant NSCLC (A549/DDP) cells was analyzed by western blot analysis. qRT-PCR, western blotting, immunofluorescence, CCK-8 assays, Annexin V/propidium iodide apoptosis assay, and Transwell migration assays were carried out to determine the function of Reelin on DDP resistance.

Results

Reelin was markedly increased in A549/DDP cells relative to A549 cells. Knockdown of Reelin enhanced DDP chemosensitivity of A549/DDP cells, whereas overexpression of Reelin enhanced DDP resistance of A549, H1299, and H460 cells. Reelin induced DDP resistance in NSCLC cells via facilitating epithelial-mesenchymal transition (EMT). Furthermore, Reelin modulated p38/GSK3β signal transduction and promoted Snail (EMT-associated transcription factor) expression. Suppression of p38/Snail reversed Reelin-induced EMT and resistance of NSCLC cells to DDP.

Conclusions

These data indicated that Reelin induces DDP resistance of NSCLC by regulation of the p38/GSK3β/Snail/EMT signaling pathway and provide evidence that Reelin suppression can be an effective strategy to suppress DDP resistance in NSCLC.

Knockdown of ubiquitin‑specific protease 51 attenuates cisplatin resistance in lung cancer through ubiquitination of zinc‑finger E‑box binding homeobox 1

Lung cancer is a devastating cancer with high morbidity and mortality. Ubiquitin‑specific protease (USP) is a type of deubiquitinating enzyme (DUB) that has been implicated in numerous cancers, including colorectal, myeloma and breast. In the present study, the expression of USP51 was determined in the lung cancer cell line A549 and cisplatin (also known as DDP)‑resistant lung cancer strain A549/DDP. The expression of zinc‑finger E‑box binding homeobox 1 (ZEB1), a transcriptional repressor, was also examined. The effects of USP51 knockdown or overexpression on proliferation and apoptosis, as well as the impact of ZEB1 overexpression and USP51 interference on apoptosis and ubiquitination were then assessed. Notably, increased expression of USP51 and ZEB1 in A549/DDP cells was observed, and treatment with DDP significantly inhibited proliferation in A549/DDP cells. In addition, knockdown of USP51 in A549/DDP cells significantly induced apoptosis, decreased ZEB1 expression and increased cleaved poly ADP‑ribose polymerase 1 (PARP1) and cleaved caspase‑3 levels. Consistently, USP51 overexpression in A549 cells displayed the opposite effects and potently attenuated DDP‑induced apoptosis. Notably, overexpression of ZEB1 in A549/DDP cells potently attenuated the effects of USP51 knockdown on apoptosis, and co‑IP experiments further demonstrated interaction between USP51 and ZEB. Lastly, knockdown of USP51 promoted ZEB1 ubiquitination, leading to ZEB1 degradation. Collectively, the present findings demonstrated that USP51 inhibition attenuated DDP resistance in A549/DDP cells via ubiquitin‑mediated degradation of ZEB1. Hence, targeting USP51 may serve as a novel therapeutic target for DDP resistance in lung cancer.

Inhibition of Wnt/β-catenin pathway reverses multi-drug resistance and EMT in Oct4+/Nanog+ NSCLC cells

Cancer drug resistance and epithelial-mesenchymal transition (EMT), a critical process of cancer invasion and metastasis, have recently been associated with the existence of cancer stem cells (CSCs). However, there are no appropriate CSC-markers of non-small cell lung cancer (NSCLC)-associated drug resistance and EMT. It is unknown if and how the drug-resistant and EMT phenotypes in NSCLC cells link to specific stemness-related pathways. Here, we found a significant elevated expression of both Oct4 and Nanog in gefitinib-resistant NSCLC cells, which displayed multi-drug resistance (MDR) properties and exhibited EMT phenotype. Ectopic co-expression of Oct4/Nanog empowered NSCLC cells with cancer stem cell properties, including self-renewal, drug resistance, EMT and high tumorigenic capacity. Following molecular mechanism investigation indicated Oct4/Nanog-regulated drug resistance and EMT change through Wnt/β-catenin signaling activation. Moreover, silencing β-catenin abrogated Oct4/Nanog-mediated MDR and EMT process in NSCLC cells. Our findings propose Wnt/β-catenin pathway as a promising therapeutic target for the treatment of progression and metastasis of NSCLC with CSC-like signatures and epithelial-mesenchymal transition phenotype.

MiR-153 reduces stem cell-like phenotype and tumor growth of lung adenocarcinoma by targeting Jagged1

Background

Cancer stem cells (CSCs) have been proposed to be responsible for tumor recurrence and chemo-resistance. Previous studies suggested that miR-153 played essential roles in lung cancer. However, the molecular mechanism of miR-153 in regulating the stemness of non-small cell lung cancer (NSCLC) remains poorly understood. In this study, we investigated the role of miR-153 in regulation of the stemness of NSCLC.

Methods

The stemness property of lung stem cancer cells was detected by sphere formation assay, immunofluorescence, and Western blot. Luciferase reporter assay was performed to investigate the direct binding of miR-153 to the 3′-UTR of JAG1 mRNA. Animal study was conducted to evaluate the effect of miR-153 on tumor growth in vivo. The clinical relevance of miR-153 in NSCLC was evaluated by Rt-PCR and Kaplan-Meier analysis.

Results

MiR-153 expression was decreased in lung cancer tissues. Reduced miR-153 expression was associated with lung metastasis and poor overall survival of lung cancer patients. Jagged1, one of the ligands of Notch1, is targeted by miR-153 and inversely correlates with miR-153 in human lung samples. More importantly, we found that miR-153 inhibited stem cell-like phenotype and tumor growth of lung adenocarcinoma through inactivating the Jagged1/Notch1 axis.

Conclusion

MiR-153 suppresses the stem cell-like phenotypes and tumor growth of lung adenocarcinoma by targeting Jagged1 and provides a potential therapeutic target in lung cancer therapy.

Se-methylselenocysteine stimulates migration and antioxidant response in HaCaT keratinocytes: Implications for wound healing

BACKGROUND

Se-methylselenocysteine (MSC), a natural organic selenium compound, is known for its anticancer effects. In the present study, we investigated the effects of MSC on cell migration, which is the most limiting step in the reepithelialization process of wound healing and the antioxidant response in HaCaT keratinocytes.

METHODS

HaCaT cells were treated with various concentrations of MSC. Cell migration and proliferation, the expression of proteins that are involved in the epidermal-mesenchymal transition (EMT) process, the extent of oxidative stress and the antioxidant response, and the associated signaling pathways were analyzed.

RESULTS

MSC (100-500 μM) increased HaCaT cell migration. MSC stimulated EMT, which was evidenced by a decrease in E-cadherin in the cells at the wound edge and increases in Snail, Twist, and matrix metalloproteinases. MSC increased the phosphorylation of Akt and glycogen synthase kinase 3β, which led to the stabilization and nuclear accumulation of β-catenin, a transcriptional coactivator involved in EMT. MSC caused a transient increase and then an eventual decrease in cellular reactive oxygen species, which appeared to be associated with the increase in nuclear factor erythroid 2-related factor 2, a key transcription factor for the antioxidant response.

CONCLUSION

Our results suggest that MSC can promote skin wound healing by stimulating keratinocyte migration and, moreover, can protect cells from excessive oxidative stress that often accompanies and impairs the wound healing process, particularly in chronic wounds, by stimulating an antioxidant response.

DNA damage response and resistance of cancer stem cells

The cancer stem cell (CSC) model defines tumors as hierarchically organized entities, containing a small population of tumorigenic CSC, or tumour-initiating cells, placed at the apex of this hierarchy. These cells may share common qualities with chemo- and radio-resistant cancer cells and contribute to self-renewal activities resulting in tumour formation, maintenance, growth and metastasis. Yet, it remains obscure what self-defense mechanisms are utilized by these cells against the chemotherapeutic drugs or radiotherapy. Recently, attention has been focused on the pivotal role of the DNA damage response (DDR) in tumorigenesis. In line with this note, an increased DDR that prevents CSC and chemoresistant cells from genotoxic pressure of chemotherapeutic drugs or radiation may be responsible for cancer metastasis. In this review, we focus on the current knowledge concerning the role of DDR in CSC and resistant cancer cells and describe the existing opportunities of re-sensitizing such cells to modulate therapeutic treatment effects.

Effects of tranilast on the epithelial-to-mesenchymal transition in peritoneal mesothelial cells

Background

We investigated the effects of tranilast on epithelial-to-mesenchymal transition (EMT) in an animal model and on the EMT signaling pathway in human peritoneal mesothelial cells (HPMCs).

Methods

We performed in vitro studies (cytotoxicity, cell morphology, and western blot analyses) on HPMCs from human omenta, along with in vivo studies (peritoneal membrane function and morphometric and immunohistochemical analyses) on Sprague Dawley rats. Thirty-two rats were divided into three groups: control (C) group (peritoneal dialysis [PD] catheter but not infused with dialysate), PD group (4.25% glucose-containing dialysate), and PD + tranilast group (4.25% glucose-containing dialysate along with tranilast).

Results

In in vitro experiments, transforming growth factor-beta 1 (TGF-β1) increased α-smooth muscle actin and Snail expression and reduced E-cadherin expression in HPMCs. TGF-β1 also reduced cell contact, induced a fibroblastoid morphology, and increased phosphorylation of Akt, Smad2, and Smad3 in HPMCs. Tranilast significantly inhibited TGF-β1-induced EMT and attenuated these morphological changes in HPMCs. In in vivo studies, after 6 weeks of experimental PD, the peritoneal membrane was significantly thicker in the PD group than in the C group. Tranilast protected against PD-induced glucose mass transfer change and histopathological changes in rats.

Conclusion

Tranilast prevented EMT both in HPMCs triggered with TGF-β1 and in rats with PD-induced peritoneal fibrosis. Thus, tranilast may be considered a therapeutic intervention that enables long-term PD by regulating TGF-β1 signaling pathways.

HIV-1 proteins gp120 and tat induce the epithelial-mesenchymal transition in oral and genital mucosal epithelial cells

The oral, cervical, and genital mucosa, covered by stratified squamous epithelia with polarized organization and strong tight and adherens junctions, play a critical role in preventing transmission of viral pathogens, including human immunodeficiency virus (HIV). HIV-1 interaction with mucosal epithelial cells may depolarize epithelia and disrupt their tight and adherens junctions; however, the molecular mechanism of HIV-induced epithelial disruption has not been completely understood. We showed that prolonged interaction of cell-free HIV-1 virions, and viral envelope and transactivator proteins gp120 and tat, respectively, with tonsil, cervical, and foreskin epithelial cells induces an epithelial-mesenchymal transition (EMT). EMT is an epigenetic process leading to the disruption of mucosal epithelia and allowing the paracellular spread of viral and other pathogens. Interaction of cell-free virions and gp120 and tat proteins with epithelial cells substantially reduced E-cadherin expression and activated vimentin and N-cadherin expression, which are well-known mesenchymal markers. HIV gp120- and tat-induced EMT was mediated by SMAD2 phosphorylation and activation of transcription factors Slug, Snail, Twist1 and ZEB1. Activation of TGF-β and MAPK signaling by gp120, tat, and cell-free HIV virions revealed the critical roles of these signaling pathways in EMT induction. gp120- and tat-induced EMT cells were highly migratory via collagen-coated membranes, which is one of the main features of mesenchymal cells. Inhibitors of TGF-β1 and MAPK signaling reduced HIV-induced EMT, suggesting that inactivation of these signaling pathways may restore the normal barrier function of mucosal epithelia.

Regulation of ATP-binding cassette subfamily B member 1 by Snail contributes to chemoresistance in colorectal cancer

Although accumulating evidence has indicated the intimate association between epithelial‐mesenchymal transition (EMT) and acquired resistance to chemotherapy for colorectal cancer (CRC), the underlying mechanisms remain elusive. Herein, we reported that Snail, a crucial EMT controller, was upregulated in CRC tissues. Colorectal cancer cells overexpressing Snail were found to be more resistant to 5‐fluorouracil (5‐Fu). Mechanistic studies reveal that Snail could increase the expression of ATP‐binding cassette subfamily B member 1 (ABCB1) rather than the other 23 chemoresistance‐related genes. Additionally, knockdown of ABCB1 significantly attenuated Snail‐induced 5‐Fu resistance in CRC cells. Oxaliplatin increased Snail and ABCB1 expression in CRC cells. Snail and ABCB1 were upregulated in 5‐Fu‐resistant HCT‐8 (HCT‐8/5‐Fu) cells and inhibition of Snail decreased ABCB1 in HCT‐8/5‐Fu cells. These results confirm the vital role played by ABCB1 in Snail‐induced chemoresistance. Further investigation into the relevant molecular mechanism revealed Snail‐mediated ABCB1 upregulation was independent of β‐catenin, STAT3, PXR, CAR and Foxo3a, which are commonly involved in modulating ABCB1 transcription. Instead, Snail upregulated ABCB1 transcription by directly binding to its promoter. Clinical analysis confirms that increased Snail expression correlated significantly with tumor size (P = .018), lymph node metastasis (P = .033), distant metastasis (P = .025), clinical stage grade (P = .024), and poor prognosis (P = .045) of CRC patients. Moreover, coexpression of Snail and ABCB1 was observed in CRC patients. Our study revealed that direct regulation of ABCB1 by Snail was critical for conferring chemoresistance in CRC cells. These findings unraveled the mechanisms underlying the association between EMT and chemoresistance, and provided potential targets for CRC clinical treatment.

Lung tumorspheres reveal cancer stem cell-like properties and a score with prognostic impact in resected non-small-cell lung cancer

The high resistance against current therapies found in non-small-cell lung cancer (NSCLC) has been associated to cancer stem-like cells (CSCs), a population for which the identification of targets and biomarkers is still under development. In this study, primary cultures from early-stage NSCLC patients were established, using sphere-forming assays for CSC enrichment and adherent conditions for the control counterparts. Patient-derived tumorspheres showed self-renewal and unlimited exponential growth potentials, resistance against chemotherapeutic agents, invasion and differentiation capacities in vitro, and superior tumorigenic potential in vivo. Using quantitative PCR, gene expression profiles were analyzed and NANOG, NOTCH3, CD44, CDKN1A, SNAI1, and ITGA6 were selected to distinguish tumorspheres from adherent cells. Immunoblot and immunofluorescence analyses confirmed that proteins encoded by these genes were consistently increased in tumorspheres from adenocarcinoma patients and showed differential localization and expression patterns. The prognostic role of genes significantly overexpressed in tumorspheres was evaluated in a NSCLC cohort (N = 661) from The Cancer Genome Atlas. Based on a Cox regression analysis, CDKN1A, SNAI1, and ITGA6 were found to be associated with prognosis and used to calculate a gene expression score, named CSC score. Kaplan–Meier survival analysis showed that patients with high CSC score have shorter overall survival (OS) in the entire cohort [37.7 vs. 60.4 months (mo), p = 0.001] and the adenocarcinoma subcohort [36.6 vs. 53.5 mo, p = 0.003], but not in the squamous cell carcinoma one. Multivariate analysis indicated that this gene expression score is an independent biomarker of prognosis for OS in both the entire cohort [hazard ratio (HR): 1.498; 95% confidence interval (CI), 1.167–1.922; p = 0.001] and the adenocarcinoma subcohort [HR: 1.869; 95% CI, 1.275–2.738; p = 0.001]. This score was also analyzed in an independent cohort of 114 adenocarcinoma patients, confirming its prognostic value [42.90 vs. not reached (NR) mo, p = 0.020]. In conclusion, our findings provide relevant prognostic information for lung adenocarcinoma patients and the basis for developing novel therapies. Further studies are required to identify suitable markers and targets for lung squamous cell carcinoma patients.

Disulfiram Overcomes Cisplatin Resistance in Human Embryonal Carcinoma Cells

Cisplatin resistance in testicular germ cell tumors (TGCTs) is a clinical challenge. We investigated the underlying mechanisms associated with cancer stem cell (CSC) markers and modalities circumventing the chemoresistance. Chemoresistant models (designated as CisR) of human embryonal carcinoma cell lines NTERA-2 and NCCIT were derived and characterized using flow cytometry, gene expression, functional and protein arrays. Tumorigenicity was determined on immunodeficient mouse model. Disulfiram was used to examine chemosensitization of resistant cells. ALDH1A3 isoform expression was evaluated by immunohistochemistry in 216 patients' tissue samples. Chemoresistant cells were significantly more resistant to cisplatin, carboplatin and oxaliplatin compared to parental cells. NTERA-2 CisR cells exhibited altered morphology and increased tumorigenicity. High ALDH1A3 expression and increased ALDH activity were detected in both refractory cell lines. Disulfiram in combination with cisplatin showed synergy for NTERA-2 CisR and NCCIT CisR cells and inhibited growth of NTERA-2 CisR xenografts. Significantly higher ALDH1A3 expression was detected in TGCTs patients' tissue samples compared to normal testicular tissue. We characterized novel clinically relevant model of chemoresistant TGCTs, for the first time identified the ALDH1A3 as a therapeutic target in TGCTs and more importantly, showed that disulfiram represents a viable treatment option for refractory TGCTs.

Dehydrogenase/reductase SDR family member 2 silencing sensitizes an oxaliplatin‑resistant cell line to oxaliplatin by inhibiting excision repair cross‑complementing group 1 protein expression

Oxaliplatin (Oxa)-based chemotherapy is widely used as the first-line treatment for colorectal cancer (CRC). However, Oxa-resistance is common for many postoperative CRC patients. To explore drug resistance in CRC, an Oxa-resistant cell line, HCT116/Oxa, was established from parental HCT116 cells. These Oxa-resistant cells exhibited characteristics of epithelial-mesenchymal transition (EMT) and a higher migratory capacity than parental cells. Protein profiles of HCT116/Oxa and HCT116 cells were compared using a tandem mass tag-based quantitative proteomics technique. The protein dehydrogenase/reductase SDR family member 2 (DHRS2) was revealed to be highly expressed in HCT116/Oxa cells. Silencing of DHRS2 in HCT116/Oxa cells effectively restored Oxa-sensitivity by suppressing the expression of excision repair cross-complementing group 1 protein via a p53-dependent pathway, and reversed the EMT phenotype. Overall, the suppression of DHRS2 expression may be a promising strategy for the prevention of Oxa-resistance in CRC.

Inhibition of PI3K/Akt/mTOR signaling pathway alleviates ovarian cancer chemoresistance through reversing epithelial-mesenchymal transition and decreasing cancer stem cell marker expression

Background

Ovarian cancer is the most common malignant tumor of the female reproductive tract. Chemoresistance is a major challenge for current ovarian cancer therapy. However, the mechanism underlying epithelial ovarian cancer (EOC) chemoresistance is not completely uncovered. The phosphatidylinositol-3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling is an important intracellular pathway in regulating cell cycle, quiescence, and proliferation. The aim of this study is to investigate the role of PI3K/Akt/mTOR signaling pathway and its association with epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) marker expression in EOC chemoresistance.

Methods

The expressions of EMT and CSC markers were detected by immunofluorescence, western blot, and quantitative real-time PCR. BEZ235, a dual PI3K/mTOR inhibitor, was employed to investigate the role of PI3K/Akt/ mTOR signaling in regulating EMT and CSC marker expression. Students’ t test and one-way ANOVA with Tukey’s post-hoc test were used to compare the data from different groups.

Results

We found that EMT and CSC marker expression were significantly enhanced in chemoresistant EOC cells, which was accompanied by the activation of PI3K/Akt/mTOR signaling. Compared with single cisplatin treatment, combined treatment with BEZ235 and cisplatin significantly disrupted the colony formation ability, induced higher ROS level and more apoptosis in chemoresistant EOC cells. Furthermore, the combination approach effectively inhibited PI3K/Akt/mTOR signaling pathway, reversed EMT, and decreased CSC marker expression in chemoresistant EOC cells compared with cisplatin mono-treatment.

Conclusions

Our results first demonstrate that EMT and enhanced CSC marker expression triggered by activated PI3K/Akt/mTOR signaling are involved in the chemoresistance of EOC, and BEZ235 in combination with cisplatin might be a promising treatment option to reverse EOC chemoresistance.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5824-9) contains supplementary material, which is available to authorized users.

Lumichrome Inhibits Human Lung Cancer Cell Growth and Induces Apoptosis via a p53-Dependent Mechanism

Lumichrome, a major derivative of riboflavin, may exhibit pharmacological activity against cancer cells. Riboflavin is a vitamin found in food, however, certain evidence has suggested its possible potentiating effects on cancer progression. Here, we have shown for the first time that unlike riboflavin, lumichrome can suppress lung cancer cell growth and reduce survival in both normal and anchorage-independent conditions. In addition, lumichrome induced apoptosis in lung cancer cells via a p53-dependent mitochondrial mechanism with substantial selectivity, shown by its lesser toxicity to the normal primary dermal papilla cells. The potency of lumichrome in killing lung cancer cells was found to be comparable to that of cisplatin, a standard chemotherapeutic drug for lung cancer treatment. With regard to the mechanism, lumichrome significantly upregulated p53 and decreased its downstream target BCL-2. Such a shift of BCL-2 family protein balance further activated caspase-9 and -3 and finally executed apoptosis. Furthermore, lumichrome potentially suppressed cancer stem cells (CSCs) in lung cancer by dramatically suppressing CSC markers together with the CSC-maintaining cell signaling namely protein kinase B (AKT) and β-catenin. To conclude, the present study has unraveled a novel role and mechanism of lumichrome against lung cancer that may benefit the development of the compound for management of the disease.

New insights into germ cell tumor genomics

BACKGROUND

Testicular germ cell tumors (GCTs) represent the most common malignancy in young men. While GCTs represent a model for curable solid tumors due to exquisite chemosensitivity, mortality for patients with GCT comprises the most life years lost for non-pediatric malignancies. Given limited options for patients with platinum-resistant disease, improved insight into GCT biology could identify novel therapeutic options for patients with platinum-resistant disease. Recent studies into molecular characteristics of both early stage and advanced germ cell tumors suggest a role for rationally targeted agents and potentially immunotherapy.

RECENT DEVELOPMENTS

Recent GWAS meta-analyses have uncovered additional susceptibility loci for GCT and provide further evidence that GCT risk is polygenic. Chromosome arm level amplifications and reciprocal loss of heterozygosity have been described as significantly enriched in GCT compared to other cancer types. Contemporary analyses confirm ubiquitous gain of isochromosome 12 and mutations in addition to previously described GCT-associated genes such as KIT and KRAS. Alterations within the TP53-MDM2 signal transduction pathway appear to be enriched among patients with platinum-resistant disease. Potentially actionable targets, including alterations in TP53-MDM2, Wnt/β-catenin, PI3K, and MAPK signaling, are present in significant proportions of patients with platinum-resistant disease and may be exploited as therapeutic options. Pre-clinical and early clinical data also suggest a potential role for immunotherapy among patients with GCTs.

CONCLUSION

Molecular characterization of GCT patients may provide biologic rationale for novel treatment options in patients with platinum-resistant disease.

CHD1L contributes to cisplatin resistance by upregulating the ABCB1-NF-κB axis in human non-small-cell lung cancer

Chromodomain helicase/ATPase DNA binding protein 1-like gene (CHD1L) is a recently identified gene associated with malignant tumor progression and patient chemotherapy resistance in human hepatocellular carcinoma (HCC). Previously, we found an association between CHD1L overexpression and poor patient survival in non-small-cell lung cancer (NSCLC). However, little is known about the relationship between CHD1L expression and chemotherapy resistance of NSCLC. By employing immunohistochemistry, we analyzed the expression of CHD1L in NSCLC samples and elucidated the roles and mechanism of CHD1L in NSCLC chemoresistance. We found that the increased expression of CHD1L is positively correlated with a shorter survival time of patients who had received chemotherapy after surgery. We also found that the expression of CHD1L was increased after cisplatin treatment in A549 cells. Conversely, the depletion of CHD1L in cisplatin-resistance cells increased the cell sensitivity to cisplatin, indicating that CHD1L plays a critical role in cisplatin resistance of NSCLC cells. Importantly, we identified the ATP-Binding Cassette Sub-Family B Member (ABCB1) gene as a potential downstream target of CHD1L in NSCLC cells. Knocking down ABCB1 coupled with ectopic expression of CHD1L enhanced the effect of cisplatin on NSCLC cells apoptosis. In addition, overexpressed CHD1L increase the transcription of c-Jun which targeted directly to the promoter of ABCB1. Our data demonstrate that CHD1L could induce cisplatin resistance in NSCLC via c-Jun-ABCB1-NF-κB axis, and may serve as a novel predictive marker and the potential therapeutic target for cisplatin resistance in NSCLC.

Multifunctional Vector for Delivery of Genome Editing Plasmid Targeting β-Catenin to Remodulate Cancer Cell Properties

Accurate and efficient delivery of genome editing plasmids to targeted cells is of critical importance in genome editing. Herein, we prepared a multifunctional delivery vector with a combination of ligand-mediated selectivity and peptide-mediated transmembrane function to effectively deliver plasmids to targeted cancerous cells. In the delivery system, the clustered regularly interspaced short palindromic repeat-associated Cas9 nuclease (CRISPR-Cas9) plasmid is combined with protamine with membrane and nuclear translocating activities and co-precipitated with CaCO₃, which is further decorated by AS1411-functionalized carboxymethyl chitosan and cell penetrating peptide (TAT)-functionalized carboxymethyl chitosan. The AS1411-mediated tumor cell/nuclear targeting and TAT-induced enhanced endocytosis result in obviously increased cellular uptake and nuclear transport. As a result, the CRISPR-Cas9 plasmid can be efficiently delivered to cancer cell nuclei to mediate genome editing, resulting in an efficacious knockout of CTNNB1 gene encoding β-catenin. More importantly, downregulation of β-catenin could effectively prevent its enrichment in nuclei and then significantly downregulate the expression of proteins, such as vimentin, Snail, MMP-2, MMP-9, CD44, Nanog, and Oct4 to prevent tumor progression and metastasis. The edited cancerous cells exhibit favorable remodulated properties including inhibited growth, suppressed migration and invasion, and reduced cancer stemness.