Can lung cancer stem cells be targeted for therapies?

YAP1 expression is associated with survival and immunosuppression in small cell lung cancer

Immunotherapy is considered a major breakthrough in the treatment of small cell lung cancer (SCLC), although its anti-tumor efficacy is limited. With a high degree of malignancy and high heterogeneity, SCLC is difficult to treat in the clinic. A new combination strategy is urgently needed to further improve the efficacy of immunotherapy in patients with SCLC. By immunofluorescence, 100 SCLC patients in a local cohort were classified into the SCLC-A (high ASCL1 expression; n = 36), SCLC-N (high NEUROD1 expression; n = 32), SCLC-P (high POU2F3 expression; n = 14), and SCLC-Y (high YAP1 expression; n = 18) subtypes. Each SCLC molecular subtype represented different prognoses, tumor microenvironment traits, and immunotherapy sensitivities. Analysis of both the local and public cohorts suggested that the SCLC-Y subtype exhibited the worst clinical outcome (p < 0.05) when compared with other subtypes. SCLC with high YAP1 expression was characterized by high PD-L1 expression, high stromal score, T-cell functional impairment, and a close relationship with immune-related pathways. YAP1 upregulated PD-L1 expression and suppressed T cell activation, thus leading to immune evasion. In in vitro experiments, blockade of YAP1 promoted cancer cell apoptosis, immune cell proliferation, T-cell activation, and cytotoxic T-cell infiltration, thus further potentiating the efficacy of immunotherapy in patients with the SCLC-Y subtype.

Machine learning-identified stemness features and constructed stemness-related subtype with prognosis, chemotherapy, and immunotherapy responses for non-small cell lung cancer patients

AIM

This study aimed to explore a novel subtype classification method based on the stemness characteristics of patients with non-small cell lung cancer (NSCLC).

METHODS

Based on the Cancer Genome Atlas database to calculate the stemness index (mRNAsi) of NSCLC patients, an unsupervised consensus clustering method was used to classify patients into two subtypes and analyze the survival differences, somatic mutational load, copy number variation, and immune characteristics differences between them. Subsequently, four machine learning methods were used to construct and validate a stemness subtype classification model, and cell function experiments were performed to verify the effect of the signature gene ARTN on NSCLC.

RESULTS

Patients with Stemness Subtype I had better PFS and a higher somatic mutational burden and copy number alteration than patients with Stemness Subtype II. In addition, the two stemness subtypes have different patterns of tumor immune microenvironment. The immune score and stromal score and overall score of Stemness Subtype II were higher than those of Stemness Subtype I, suggesting a relatively small benefit to immune checkpoints. Four machine learning methods constructed and validated classification model for stemness subtypes and obtained multiple logistic regression equations for 22 characteristic genes. The results of cell function experiments showed that ARTN can promote the proliferation, invasion, and migration of NSCLC and is closely related to cancer stem cell properties.

CONCLUSION

This new classification method based on stemness characteristics can effectively distinguish patients' characteristics and thus provide possible directions for the selection and optimization of clinical treatment plans.

Identification of GPD1L as a Potential Prognosis Biomarker and Associated with Immune Infiltrates in Lung Adenocarcinoma

Lung adenocarcinoma (LUAD) is one of the most prevalent pathological kinds of lung cancer, which is a common form of cancer that has a high death rate. Over the past several years, growing studies have indicated that GPD1L was involved in the advancement of a number of different cancers. However, its clinical significance in LUAD has not been investigated. In this study, following an examination of the TGCA datasets, we found that GPD1L displayed a dysregulated state in a wide variety of cancers; this led us to believe that GPD1L is an essential regulator in the progression of malignancies. In addition, we found that the expression of GPD1L was much lower in LUAD tissues when compared with nontumor specimens. According to the findings of ROC tests, GPD1L was able to effectively identify LUAD specimens from nontumor samples with an AUC value of 0.828 (95% confidence interval: 0.793 to 0.863). On the basis of the clinical study, a low expression of GPD1L was clearly related with both the N stage and the clinical stage. Moreover, based on the findings of a Kaplan-Meier survival study, elevated GPD1L expression was a strong indicator of considerably improved overall survival (OS) and disease-specific survival (DSS). GPD1L expression and clinical stages were found to be independent prognostic indicators for overall survival and disease-free survival in LUAD patients, according to multivariate analyses. Based on multivariate analysis, the C-indexes and calibration plots of the nomogram demonstrated an effective prediction performance for LUAD patients. Besides, the expression of GPD1L was positively related to mast cells, eosinophils, Tcm, TFH, iDC, DC, and macrophages, while negatively associated with Th2 cells, NK CD56dim cells, Tgd, Treg, and neutrophils. Finally, qRT-PCR was able to demonstrate that GPD1L had a significant amount of expression in LUAD. Additionally, according to the results of functional tests, overexpression of GPD1L had a significant inhibiting effect on the proliferation of LUAD cells. In general, the results of our study suggested that GPD1L had the potential to serve as a diagnostic and prognostic marker for LUAD.

Alpha-enolase (ENO1), identified as an antigen to monoclonal antibody 12C7, promotes the self-renewal and malignant phenotype of lung cancer stem cells by AMPK/mTOR pathway

BACKGROUND

Tumor-associated antigens (TAAs) can be targeted in cancer therapy. We previously identified a monoclonal antibody (mAb) 12C7, which presented anti-tumor activity in lung cancer stem cells (LCSCs). Here, we aimed to identify the target antigen for 12C7 and confirm its role in LCSCs.

METHODS

Immunofluorescence was used for antigen localization. After targeted antigen purification by electrophoresis and immunoblot, the antigen was identified by LC-MALDI-TOF/TOF mass spectrometry, immunofluorescence, and immunoprecipitation. The overexpression or silence of ENO1 was induced by lentiviral transduction. Self-renewal, growth, and invasion of LCSCs were evaluated by sphere formation, colony formation, and invasion assay, respectively. High-throughput transcriptome sequencing (RNA-seq) and bioinformatics analysis were performed to analyze downstream targets and pathways of targeted antigen.

RESULTS

Targeted antigen showed a surface antigen expression pattern, and the 43-55 kDa protein band was identified as α-enolase (ENO1). Self-renewal, growth, and invasion abilities of LCSCs were remarkably inhibited by ENO1 downregulation, while enhanced by ENO1 upregulation. RNA-seq and bioinformatics analysis eventually screened 4 self-renewal-related and 6 invasion-related differentially expressed genes. GSEA analysis and qRT-PCR verified that ENO1 regulated self-renewal, invasion-related genes, and pathways. KEGG pathway analysis and immunoblot demonstrated that ENO1 inactivated AMPK pathway and activated mTOR pathway in LCSCs.

CONCLUSIONS

ENO1 is identified as a targeted antigen of mAb 12C7 and plays a pivotal role in facilitating self-renewal, growth, and invasion of LCSCs. These findings provide a potent therapeutic target for the stem cell therapy for lung cancer and have potential to improve the anti-tumor activity of 12C7.

Dibenzazepine Attenuates Against Cisplatin-Induced Nephrotoxicity in Rats: Involvement of NOTCH Pathway

Cisplatin is one of the standard anti-cancer agents that are used to treat variety of solid tumors. Nevertheless, due to the accumulation of cisplatin in the renal epithelial cells, nephrotoxicity was found to be the main side effect that limits its clinical use. The current study was conducted to assess the potential nephroprotective effect of dibenzazepine, a Notch inhibitor, against cisplatin-induced nephrotoxicity in rats as well as the possible mechanisms underlying this nephroprotection. The rats were pre-treated with 2 mg/kg dibenzazepine for 7 days before giving a single nephrotoxic dose of cisplatin (7 mg/kg). Cisplatin induced acute nephrotoxicity, where blood urea nitrogen and serum creatinine levels were significantly increased. Besides, lipid peroxidation was markedly elevated and the levels of reduced glutathione and catalase were significantly reduced. Also, the tissue levels of the pro-inflammatory mediators; IL-1β, TNF-α, and NF-kB, were significantly increased in the cisplatin group. The pre-treatment with dibenzazepine significantly mitigated the nephrotoxic effects of cisplatin, the oxidative stress and inflammatory status as well as decreased caspase-3 expression, as compared to the cisplatin group. Furthermore, the up-regulation of Notch-1 and Hes-1 was found to be involved in cisplatin-induced nephrotoxicity and their expression was significantly reduced by dibenzazepine. The nephroprotective effect of dibenzazepine was further confirmed by the histopathological assessment. Moreover, dibenzazepine pre-treatment of hela and PC3 cells in vitro did not antagonize the cisplatin anti-cancer activity. In conclusion, these findings show that dibenzazepine provides protection against cisplatin-induced nephrotoxicity. Moreover, the up-regulation of the Notch pathway was shown to play a role in the pathogenesis of cisplatin-induced renal injury.

Nanoparticles for Manipulation of the Developmental Wnt, Hedgehog, and Notch Signaling Pathways in Cancer

The Wnt, Hedgehog, and Notch signaling pathways play a crucial role in early development and the maintenance of adult tissues. When dysregulated, these developmental signaling pathways can drive the formation and progression of cancer by facilitating cell survival, proliferation, and stem-like behavior. While this makes these pathways promising targets for therapeutic intervention, their pharmacological inhibition has been challenging due to the substantial complexity that exists within each pathway and the complicated crosstalk that occurs between the pathways. Recently, several small molecule inhibitors, ribonucleic acid (RNA) molecules, and antagonistic antibodies have been developed that can suppress these signaling pathways in vitro, but many of them face systemic delivery challenges. Nanoparticle-based delivery vehicles can overcome these challenges to enhance the performance and anti-cancer effects of these therapeutic molecules. This review summarizes the mechanisms by which the Wnt, Hedgehog, and Notch signaling pathways contribute to cancer growth, and discusses various nanoparticle formulations that have been developed to deliver small molecules, RNAs, and antibodies to cancer cells to inhibit these signaling pathways and halt tumor progression. This review also outlines some of the challenges that these nanocarriers must overcome to achieve therapeutic efficacy and clinical translation.

High-sensitive and multiplex biosensing assay of NSCLC-derived exosomes via different recognition sites based on SPRi array

Non-small cell lung cancer (NSCLC) have been reported to secret a high concentration of exosomes into blood circulatory system, which is one of sensitive and non-invasive biomarkers for NSCLC's early-stage diagnosis. But it is still lack of feasible and accurate methods to analyze the different NSCLC cells-derived exosomes. Herein, we built a SPRi biosensing assay for high-sensitive and multiplex characterizations of NSCLC-derived exosomes by bioaffinity interactions of antibodies and different recognition sites. By this way, the exosomes derived from normal lung and NSCLC cells can be effectively distinguished through precise identification of the exosomal protein pattern. And the multiplex characterizations of NSCLC-related exosomes are also achieved by anti-CD63, anti-EGFR and anti-EpCAM modified SPRi array. The limit of detection (LOD) of this SPRi-based biosensor approaches to the level of 10⁴ particles/μL with the help of functionalized gold nanoparticles. Besides, the developed biosensing assay was successfully applied in the determination of exosomes purified from clinical plasma samples. This SPRi biosensing strategy might offer a potential alternative for massive high-throughput screening for NSCLC in clinical specimens.

PM2.5 induces EMT and promotes CSC properties by activating Notch pathway in vivo and vitro

Fine particulate matter (PM2.5) has been closely linked to increased morbidity and mortality of lung cancer worldwide. However, the role of PM2.5 in the etiology of lung cancer and the mechanism involved in PM2.5 induced lung cancer are largely unknown. In this study, we performed chronic exposure animal model to investigate the carcinogenetic mechanisms of PM2.5 by targeting the induction of epithelial-mesenchymal transition (EMT) and cancer stem cells (CSC) properties through Notch1 signal pathway. The antagonism of Notch1 signal pathway was carried out in vitro cell lines of A549 and BEAS-2B to block EMT and CSC. We found that chronic PM2.5 exposure mice lung tissue pathology showed atypical hyperplasia of bronchiolar epithelium. Then, we discovered that chronic PM2.5 exposure induced notable EMT event and obvious CSC properties indicating the developing process of cell malignant behaviors. EMT characterized with decreased protein expression of E-cadherin and increased protein expression of Vimentin. CSC properties induced by chronic PM2.5 exposure characterized with increased cell-surface markers (ABCG2 and ALDH1A1) and self-renewal genes (SOX2 and OCT4). Furthermore, PM2.5 exposure activate Notch signal pathway by increasing expression of Notch1 and Hes1. At last, we blocked Notch signal pathway by inhibitor RO4929097 in vitro to explore the underlying mechanism mediating PM2.5 induced EMT and CSC. We found that blocking Notch1 could prevent PM2.5 induced malignant behaviors including EMT and CSC in A549 and BEAS-2B. These data revealed that the induction of EMT and CSC properties were involved in the lung cancer risk of PM2.5 in vivo, and blocking-up Notch1 may negatively regulate EMT and CSC to suppress the invasion and migration in vitro, thereby putatively serving as a novel therapeutic target for PM2.5 induced lung cancer.

Head and neck cancer management and cancer stem cells implication

Head and neck squamous cell carcinomas (HNSCCs) arise in the mucosal linings of the upper aerodigestive tract and are heterogeneous in nature. Risk factors for HNSCCs are smoking, excessive alcohol consumption, and the human papilloma virus. Conventional treatments are surgery, radiotherapy, chemotherapy, or a combined modality; however, no international standard mode of therapy exists. In contrast to the conventional model of clonal evolution in tumor development, there is a newly proposed theory based on the activity of cancer stem cells (CSCs) as the model for carcinogenesis. This “CSC hypothesis” may explain the high mortality rate, low response to treatments, and tendency to develop multiple tumors for HNSCC patients. We review current knowledge on HNSCC etiology and treatment, with a focus on CSCs, including their origins, identifications, and effects on therapeutic options.

Characterization of CD133+/CD44+ human prostate cancer stem cells with ATR-FTIR spectroscopy

Current cancer treatments destroy the tumor mass but cannot prevent the recurrence of cancer. The heterogeneous structure of the tumor mass includes cancer stem cells that are responsible for tumor relapse, treatment resistance, invasion and metastasis. The biology of these cells is still not fully understood; therefore, effective treatments cannot be developed sufficiently. Herein, attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, combined with unsupervised multivariate analysis, was applied to prostate cancer stem cells (CSCs), non-stem cancer cells (non-CSCs) and normal prostate epithelial cells to elucidate the molecular mechanisms and features of CSCs, which are crucial to improving the target specific therapies. This work revealed the spectral differences in the cellular mechanisms and biochemical structures among three different cell types. Particularly, prostate CSCs exhibit differences in the lipid composition and dynamics when compared to other cell types. CSCs also harbor pronounced differences in their major cellular macromolecules, including differences in the protein amount and content (mainly α-helices), the abundance of nucleic acids (DNA/RNA), altered nucleic acid conformation and carbohydrate composition. Interestingly, macromolecules containing the C[double bond, length as m-dash]O groups and negatively charged molecules having the COO^- groups are abundant in prostate CSCs in comparison to prostate non-CSCs and normal prostate cells. Overall, this study demonstrates the potential use of ATR-FTIR spectroscopy as a powerful tool to obtain new insights into the understanding of the CSC features, which may provide new strategies for cancer treatment by selectively targeting the CSCs.

FOXC1 induces cancer stem cell-like properties through upregulation of beta-catenin in NSCLC

Background

Accumulating evidence suggests that cancer stem cells (CSCs) play a critical role in tumor initiation, progression and therapy, and recent studies have indicated that Forkhead box C1 (FOXC1) is strongly associated with CSCs. This study investigates the regulatory effects of FOXC1 on CSC-like properties in non-small cell lung cancer (NSCLC).

Methods

We analyzed FOXC1 expression in NSCLC using the Cancer Genome Atlas (TCGA) database on UALCANC and performed survival analyses of NSCLC patients on Human Protein Atlas. CSC-like properties were analyzed based on CSC marker-positive cell population, self-renewal ability, stemness-related gene expression, tumorigenicity and drug resistance. The percentage of CD133⁺ cells was analyzed by flow cytometric analysis. Self-renewal ability was detected by sphere-formation analysis. Real-time PCR, western blotting and immunohistochemical staining were employed to detect mRNA and protein levels. Tumorigenicity was determined based on a xenograft formation assay, and effects of FOXC1 on drug resistance were assessed by cell viability and apoptosis assays. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays were used to investigate the binding of FOXC1 to beta-catenin promoter.

Results

FOXC1 expression was found to be elevated in NSCLC tissues and negatively correlated with patient survival. FOXC1 knockdown reduced CD133⁺ cell percentage, suppressed self-renewal ability, decreased expression of stemness-related genes (Oct4, NANOG, SOX2 and ABCG2) and inhibited NSCLC cell tumorigenicity in vivo. Moreover, FOXC1 knockdown increased cisplatin and docetaxel sensitivity and reduced gefitinib resistance, whereas FOXC1 overexpression enhanced CSC-like properties. Luciferase reporter and ChIP assays showed beta-catenin to be a direct transcriptional target of FOXC1. Furthermore, overexpression of beta-catenin reversed the CSC-like property inhibition induced by FOXC1 knockdown, and knockdown of beta-catenin attenuated the CSC-like properties induced by FOXC1 overexpression.

Conclusions

This study demonstrates that FOXC1 induces CSC-like properties in NSCLC by promoting beta-catenin expression. The findings indicate that FOXC1 is a potential molecular target for anti-CSC-based therapies in NSCLC.

[Research Progress in the Therapeutic Strategy Based on Targeting at Lung Cancer Stem Cell]

With high morbidity and mortality, lung cancer is a major threat to human health and one of the focuses of tumor researches. Lung cancer stem cells (LCSCs) are regarded as a subpopulation of cells within lung cancer tissues with the capacity of self-renewal and differentiation, and might be related to tumorigenesis and heterogeneity of lung cancer. Tumor recurrence, metastasis and drug resistance of lung cancers could be clarified by LCSC hypothesis. Thus it's therapeutically prospective to target at these cells. This review summarizes the biomarkers of LCSCs and their aberrant signal pathways, as well as the therapeutic strategies targeting at LCSCs.

The mechanisms for lung cancer risk of PM2.5 : Induction of epithelial-mesenchymal transition and cancer stem cell properties in human non-small cell lung cancer cells

Fine particulate matter (PM_2.5 ) is a major component of air pollutions that are closely associated with increased risk of lung cancer. However, the role of PM_2.5 in the etiology of lung cancer is largely unknown. In this study, we performed acute (24 hours) and chronic (five passages) exposure models to investigate the carcinogenetic mechanisms of PM_2.5 by targeting the induction of epithelial-mesenchymal transition (EMT) and cancer stem cells (CSC) properties in human non-small cell lung cancer cell line A549. We found that both acute and chronic PM_2.5 exposure enhanced cell migration and invasion, decreased mRNA expression of epithelial markers and increased mRNA expression of mesenchymal markers. Chronic PM_2.5 exposure further induced notable EMT morphology and CSC properties, indicating the developing process of cell malignant behaviors from acute to chronic PM_2.5 exposure. CSC properties induced by chronic PM_2.5 exposure characterized with increased cell-surface markers (CD44, ABCG2), self-renewal genes (SOX2 and OCT4), side population cells and neoplastic capacity. Furthermore, the levels of three stemness-associated microRNAs, Let-7a, miR-16 and miR-34a, were found to be significantly downregulated by chronic PM_2.5 exposure, with microarray data analysis from TCGA database showing their lower expression in human lung adenocarcinoma tissues than that in the adjacent normal lung tissues. These data revealed that the induction of EMT and CSC properties were involved in the lung cancer risk of PM_2.5 , and implicated CSC properties and related microRNAs as possible biomarkers for carcinogenicity prediction of PM_2.5 .

Breast cancer stem-like cells can promote metastasis by activating platelets and down-regulating antitumor activity of natural killer cells

OBJECTIVE

To investigate whether cancer stem cells (CSCs) more efficiently activating platelets and evading immune surveillance than non-CSCs thus promoting metastasis.

METHODS

We enriched and identified sphere-forming cells (SFCs) and coincubated washed platelets with several platelet activators including collagen, 4T1 and SFCs. Platelet-coating tumor cells, platelet activation and TGF-β1 release were analyzed. Then natural kell cells (NK) were incubated with supernatants of different activated platelet samples what we called sample release (SR). The degranulation assay and NKG2D expression on NK cells were conducted by flow cytometry. Finally tissue factor (TF) expression of SFCs or 4T1 were evaluated by western blot.

RESULTS

Breast cancer cell line 4T1 could form spheres in serum-free medium at low adherence. Sphere-forming cells expressed high levels of the CD24-/lowCD44 + stem cell phenotype. Both sphere-forming cells or 4T1 were coated with abundant platelets while sphere-forming cells induced significantly higher expression of platelet activating receptor CD62p than 4T1 did (P < 0.01). And sphere-forming cells induced platelets to produce more TGF-β1 than 4T1 did (P < 0.01). Furthermore, sample releases induced by sphere-forming cells caused more vigorous inhibition of NK cells antitumor reactivity (P < 0.05) and reduced NKG2D expression (P < 0.01). The final results showed that sphere-forming cells expressed higher levels of TF than 4T1 (P < 0.05).

CONCLUSION

Our findings indicate that CSCs could efficiently activate platelets, induce platelets to secrete more TGF-β1, decrease NKG2D expression and inhibit antitumor activity of NK cell, compared with 4T1. And higher levels of TF expression of CSCs may account for this correlation of CSCs and platelets.

Relationship between microvessel density and cancer stem cells in tumor angiogenesis: a meta-analysis

Aim: Several studies have shown that cancer stem cells (CSCs) promote tumor angiogenesis and are involved in tumor growth. A meta-analysis was conducted to evaluate the association between cancer stem cell markers expression and microvessel density (MVD). Methods: Relevant literature was identified from diverse databases. The Stata 12.0 and Review Manager 5.3 software were used to performed meta-analysis. Results: Sixteen studies investigating the correlation between CSCs and tumor angiogenesis were included in a total of 1409 cases. The result showed that positive CSC markers expression were associated with increased MVD count in human tumors and CSC-transplanted mouse tumor models (p < 0.0001). Conclusion: CSCs may be associated with angiogenesis during the growth and development of tumors.

Cancer stem cells: a metastasizing menace!

Cancer is one of the leading causes of death worldwide, and is estimated to be a reason of death of more than 18 billion people in the coming 5 years. Progress has been made in diagnosis and treatment of cancer; however, a sound understanding of the underlying cell biology still remains an unsolved mystery. Current treatments include a combination of radiation, surgery, and/or chemotherapy. However, these treatments are not a complete cure, aimed simply at shrinking the tumor and in majority of cases, there is a relapse of tumor. Several evidences suggest the presence of cancer stem cells (CSCs) or tumor‐initiating stem‐like cells, a small population of cells present in the tumor, capable of self‐renewal and generation of differentiated progeny. The presence of these CSCs can be attributed to the failure of cancer treatments as these cells are believed to exhibit therapy resistance. As a result, increasing attention has been given to CSC research to resolve the therapeutic problems related to cancer. Progress in this field of research has led to the development of novel strategies to treat several malignancies and has become a hot topic of discussion. In this review, we will briefly focus on the main characteristics, therapeutic implications, and perspectives of CSCs in cancer therapy.

Targeting colorectal cancer stem cells using curcumin and curcumin analogues: insights into the mechanism of the therapeutic efficacy

Colorectal cancer is one of the commonest cancers in the world and it is also a common cause of cancer-related death worldwide. Despite advanced treatment strategies, the disease is rarely cured completely due to recurrence. Evidence shows that this is due to a small population of cells, called cancer stem cells (CSCs), in the tumour mass that have the self-renewal and differentiation potential to give rise to a new tumour population. Many pre-clinical and clinical studies have used curcumin and its analogues as anti-cancer agents in various types of cancer, including colorectal cancer. Intriguingly, curcumin and its analogues have also recently been shown to be effective in lowering tumour recurrence by targeting the CSC population, hence inhibiting tumour growth. In this review, we highlight the efficacy of curcumin and its analogues in targeting colorectal CSC and also the underlying molecular mechanism involved. Curcumin, in the presence or absence of other anti-cancer agents, has been shown to reduce the size of tumour mass and growth in both in vivo and in vitro studies by affecting many intracellular events that are associated with cancer progression and CSC formation. An insight into the molecular mechanism has unraveled the mode of action via which curcumin could affect the key regulators in CSC, importantly; (1) the signaling pathways, including Wnt/β-catenin, Sonic Hedgehog, Notch and PI3K/Akt/mTOR, (2) microRNA and (3) the epithelial-mesenchymal transition at multiple levels. Therefore, curcumin could play a role as chemosensitiser whereby the colorectal CSCs are now sensitised towards the anti-cancer therapy, therefore, combination therapy using anti-cancer agent with curcumin could be much more effective than treatment using a single cancer agent. This potential treatment modality can be further developed by employing an effective delivery system using a nanotechnology based approach to treat colorectal cancer.

Influence of As2O3 combined with ginsenosides Rg3 on inhibition of lung cancer NCI-H1299 cells and on subsistence of nude mice bearing hepatoma

OBJECTIVES

To study the effect of arsenic trioxide (As2O3) combined with ginsenosides Rg3 on inhibiting the NCI-H1299 lung cancer cells and subsistence in nude mice bearing hepatoma.

METHODS

MTT method was used to measure the inhibition effect of As2O3 combined Rg3 on NCI-H1299 cells, and the proliferation inhibiting effect was observed via establishing the transplanted tumor model in vitro. A total of 40 tumor-bearing nude mice were randomly divided into normal saline group, As2O3, Rg3 and As2O3+Rg3 group. Transplantation tumor model of lung cancer in nude mice was constructed, followed by injection of certain concentrations of normal saline, As2O3, ginseng saponin Rg3 and As2O3+Rg3 every day. The survival duration and the tumors size of the mice were recorded and the Kaplan-Meier curve was made; microscopic observation of apoptosis of tumor cells in vivo was done using TUNEL staining.

RESULTS

After 72 h of injection, inhibition rate of tumor cell in normal saline group, As2O3 group, Rg3 group and As2O3+Rg3 group was (5.66±0.31)%, (65.58±4.75)%, (44.69±3.32)% and (82.67±5.43)%, respectively. Inhibition rate of tumor cell in As2O3 group, Rg3 group and As2O3+Rg3 group was significantly higher than that of normal saline group (P<0.01); inhibition rate of tumor cells of As2O3+Rg3 group was significantly higher than that of the two groups given As2O3 or Rg3 alone (P<0.01). The tumor volume of As2O3 group, Rg3 group and As2O3+Rg3 group shrank to (65.38±3.25)%, (77.68±3.43)% and (42.65±3.55)% of the original, tumor volume of saline group was 1.21 times of the original size (P<0.01); Median survival of saline group, Rg3 group, As2O3 group were significantly shorter than that of As2O3+Rg3 group (P<0.01); co-ordinated intervention ability of As2O3+Rg3 on NCI-H1299 cell was significantly higher than that of As2O3 or Rg3, separately.

CONCLUSIONS

As2O3 combined with Rg3 can significantly inhibit proliferation of NCI-H1299 cells in lung cancer, prolong survival of tumor-bearing nude mice, and promote tumor cell apoptosis, and have significant effect on lung cancer treatment.

Enrichment and characterization of cancer stem cells from a human non-small cell lung cancer cell line

Tumor cells from the same origin comprise different cell populations. Among them, cancer stem cells (CSCs) have higher tumorigenicity. It is necessary to enrich CSCs to determine an effective way to suppress and eliminate them. In the present study, using the non-adhesive culture system, tumor spheres were successfully generated from human A549 non-small cell lung cancer (NSCLC) cell line within 2 weeks. Compared to A549 adherent cells, sphere cells had a higher self-renewal ability and increased resistance to cytotoxic drugs. Sphere cells were more invasive and expressed stem cell markers including octamer‑binding transcription factor 4 (Oct4) and sex-determining region Y-box 2 (Sox2) at high levels. CD133, a disputed marker of lung CSCs, was also upregulated. Tumor sphere cells showed higher tumorigenic ability in vivo, indicating that more CSCs were enriched in the sphere cells. More blood vessels were formed in the tumor generated by sphere cells suggesting the interaction between CSCs and blood vessel. A reliable model of enriching CSCs from the human A549 NSCLC cell line was established that was simple and cost-effective compared to other methods.

The role of the immune system in non-small cell lung carcinoma and potential for therapeutic intervention

Over a hundred years after the first description of this disease, lung cancer represents one of the major challenges in oncology. Radical treatment cannot be introduced in more than 70% of cases and overall survival rate does not exceed 15%. The immunosurveillance of lung cancer may be effective in early oncogenesis but is inhibited in the course of developing a clinically detectable tumor. Very low and heterogonous antigenicity of lung cancer cells leads to passive escape from anti-cancer immune defense. The cytotoxic lymphocytes (CTLs) that play a main role in the anticancer response are actively suppressed in the tumor environment and following regulatory mechanisms inhibit the recognition of tumor antigens by antigen presenting cells. The population of regulatory T cells (Tregs) is augmented and the expression of transcription factor-Foxp3 is markedly increased on tumor cells and tumor infiltrating lymphocytes (TIL). It is accomplished by M2 macrophage polarization, the activity of myeloid derived suppressor cells (MDSCs) and a significantly elevated concentration of cytokines: transforming growth factor beta (TGFβ) and IL-10 in the tumor microenvironment. Very active suppression of immune protection is the predominant role of the programmed death 1 (PD-1)-PD-L1 pathway. The blockage of this pathway was found to be an effective treatment approach; therefore the monoclonal antibodies are being intensively investigated in lung cancer patients. Cytotoxic T lymphocyte antigen-4 (CTLA-4) is the molecule capable of inhibiting the activation signal. The antibody anti-CTLA-4 improves CTLs function in solid tumors and lung cancer patients may benefit from use of this agent. The second way in lung cancer immunotherapy is production of anti-cancer vaccines using recognized cancer antigens: MAGE-A3, membrane associated glycoprotein (MUC-1), and EGF. It was recently shown in ongoing clinical trials that combined therapies: immune- and chemotherapy, radiotherapy or targeted therapy seem to be effective. Immunotherapy in lung cancer has an individual character-there is a need to assess the patient's immune status prior to implementation of immunomodulating therapy.

Coating Solid Lipid Nanoparticles with Hyaluronic Acid Enhances Antitumor Activity against Melanoma Stem-like Cells

Successful anticancer chemotherapy requires targeting tumors efficiently and further potential to eliminate cancer stem cell (CSC) subpopulations. Since CD44 is present on many types of CSCs, and it binds specially to hyaluronic acid (HA), we tested whether coating solid lipid nanoparticles with hyaluronan (HA-SLNs)would allow targeted delivery of paclitaxel (PTX) to CD44-overexpressing B16F10 melanoma cells. First, we developed a model system based on melanoma stem-like cells for experiments in vitro and in mouse xenografts, and we showed that cells expressing high levels of CD44 (CD44⁺) displayed a strong CSC phenotype while cells expressing low levels of CD44 (CD44^-) did not. This phenotype included sphere and colony formation, higher proportion of side population cells, expression of CSC-related markers (ALDH, CD133, Oct-4) and tumorigenicity in vivo. Next we showed that administering PTX-loaded HA-SLNs led to efficient intracellular delivery of PTX and induced substantial apoptosis in CD44⁺ cells in vitro. In the B16F10-CD44⁺ lung metastasis model, PTX-loaded HA-SLNs targeted the tumor-bearing lung tissues well and subsequently exhibited significant antitumor effects with a relative low dose of PTX, which provided significant survival benefit without evidence of adverse events. These findings suggest that the HA-SLNs targeting system shows promise for enhancing cancer therapy.

Porous PLGA microparticles to encapsulate doxorubicin and polyethylenimine/miR-34a for inhibiting the proliferation and migration of lung cancer

Porous PLGA microparticles were successfully prepared for achieving the co-delivery of doxorubicin and PEI25K/miR-34a, using ammonium bicarbonate as a porogen.

Stemness and plasticity of lung cancer cells: paving the road for better therapy

Lung cancer is a devastating disease that is responsible for around 160,000 deaths each year in United States. The discovery that lung cancer, like most other solid tumors, contains a subpopulation of cancer stem cells or cancer stem-like cells (CSCs/CS-LCs) that if eliminated could lead to a cure has brought new hope. However, the exact nature of the putative lung CSCs/CS-LCs is not known and therefore therapies to eliminate this subpopulation have been elusive. A limited knowledge and understanding of cancer stem cell properties and tumor biology may be responsible for the limited clinical success. In this review we discuss the stemness and plasticity properties of lung cancer cells that are critical aspects in terms of developing effective therapies. We suggest that the available experimental evidence obtained from lung cancer cell lines and patients’ derived primary cultures does not support a tumor model consistent with the classical CSC model. Instead, all lung cancer cells may be extremely versatile and new models of cancer stem cells may be better working models.

Human marrow stromal cells downsize the stem cell fraction of lung cancers by fibroblast growth factor 10

The functional interplay between cancer cells and marrow stromal cells (MSCs) has attracted a great deal of interest due to the MSC tropism for tumors but remains to be fully elucidated. In this study, we investigated human MSC-secreted paracrine factors that appear to have critical functions in cancer stem cell subpopulations. We show that MSC-conditioned medium reduced the cancer stem cell-enriched subpopulation, which was detected as a side population and quiescent (G0) cell cycle fraction in human lung cancer cells by virtue of fibroblast growth factor 10 (FGF10). This reduction of the stem cell-enriched fraction was also observed in lung cancer cells supplemented with recombinant human FGF10 protein. Moreover, supplementary FGF10 attenuated the expression of stemness genes encoding transcription factors, such as OCT3/4 and SOX2, and crippled the self-renewal capacity of lung cancer cells, as evidenced by the impaired formation of floating spheres in the suspension culture. We finally confirmed the therapeutic potential of the FGF10 treatment, which rendered lung cancer cells prone to a chemotherapeutic agent, probably due to the reduced cancer stem cell subpopulation. Collectively, these results add further clarification to the molecular mechanisms underlying MSC-mediated cancer cell kinetics, facilitating the development of future therapies.

Overview of cancer stem cells (CSCs) and mechanisms of their regulation: implications for cancer therapy

The identification of small subpopulations of cancer stem cells (CSCs) from blood mononuclear cells in human acute myeloid leukemia (AML) in 1997 was a landmark observation that recognized the potential role of CSCs in tumor aggressiveness. Two critical properties contribute to the functional role of CSCs in the establishment and recurrence of cancerous tumors: their capacity for self-renewal and their potential to differentiate into unlimited heterogeneous populations of cancer cells. These findings suggest that CSCs may represent novel therapeutic targets for the treatment and/or prevention of tumor progression, since they appear to be involved in cell migration, invasion, metastasis, and treatment resistance-all of which lead to poor clinical outcomes. The identification of CSC-specific markers, the isolation and characterization of CSCs from malignant tissues, and targeting strategies for the destruction of CSCs provide a novel opportunity for cancer research. This overview describes the potential implications of several common CSC markers in the identification of CSC subpopulations that are restricted to common malignant diseases, e.g., leukemia, and breast, prostate, pancreatic, and lung cancers. The role of microRNAs (miRNAs) in the regulation of CSC function is also discussed, as are several methods commonly used in CSC research. The potential role of the antidiabetic drug metformin- which has been shown to have effects on CSCs, and is known to function as an antitumor agent-is discussed as an example of this new class of chemotherapeutics.

[Correlations between OCT4 expression and clinicopathological factors and prognosis of patients with lung adenocarcinoma]

背景与目的

肺腺癌发病率不断升高, 而OCT4是调控干细胞自我更新的关键基因, 在癌干细胞的增殖分化过程中起重要调节作用。本研究目的为检测肺腺癌组织中OCT4表达, 并分析其与肺腺癌患者转移、化疗疗效及预后的相关性。

方法

采用免疫荧光方法检测肺腺癌组织OCT4表达。卡方检验OCT4表达与临床病理指标的关系, Kaplan-Meier生存曲线计算生存率, 采用Cox分析评估各指标与患者生存之间的关系。

结果

126例肺腺癌组织中, 91例可观察到OCT4阳性细胞。OCT4表达与肺腺癌患者转移及化疗耐药密切相关, 且与患者无病生存期和生存期呈明显负相关。

结论

OCT4表达与肺腺癌患者的转移及化疗耐药相关, 提示预后不良。

Gene polymorphisms and chronic obstructive pulmonary disease

The genetic component was suggested to contribute to the development of chronic obstructive pulmonary disease (COPD), a major and growing public health burden. The present review aims to characterize the evidence that gene polymorphisms contribute to the aetiology of COPD and related traits, and explore the potential relationship between certain gene polymorphisms and COPD susceptibility, severity, lung function, phenotypes, or drug effects, even though limited results from related studies lacked consistency. Most of these studies were association studies, rather than confirmatory studies. More large-sized and strictly controlled studies are needed to prove the relationship between gene polymorphisms and the reviewed traits. More importantly, prospective confirmatory studies beyond initial association studies will be necessary to evaluate true relationships between gene polymorphisms and COPD and help individualized treatment for patients with COPD.

Biomarkers and molecular testing for early detection, diagnosis, and therapeutic prediction of lung cancer

The search for biomarkers in the management of lung cancer involves the use of multiple platforms to examine changes in gene, protein, and microRNA expression. Multiple studies have been published in an attempt to describe early detection, diagnostic, prognostic, and predictive biomarkers using chiefly tissues and blood elements. Studies are characterized by a lack of commonality of specific biomarkers, and a lack of validated, clinically useful markers. The future of biomarker discovery as a means of tailoring therapy for patients with lung cancer will involve next-generation sequencing along with collaborative efforts to integrate and validate candidate markers.

Wrangling phosphoproteomic data to elucidate cancer signaling pathways

The interpretation of biological data sets is essential for generating hypotheses that guide research, yet modern methods of global analysis challenge our ability to discern meaningful patterns and then convey results in a way that can be easily appreciated. Proteomic data is especially challenging because mass spectrometry detectors often miss peptides in complex samples, resulting in sparsely populated data sets. Using the R programming language and techniques from the field of pattern recognition, we have devised methods to resolve and evaluate clusters of proteins related by their pattern of expression in different samples in proteomic data sets. We examined tyrosine phosphoproteomic data from lung cancer samples. We calculated dissimilarities between the proteins based on Pearson or Spearman correlations and on Euclidean distances, whilst dealing with large amounts of missing data. The dissimilarities were then used as feature vectors in clustering and visualization algorithms. The quality of the clusterings and visualizations were evaluated internally based on the primary data and externally based on gene ontology and protein interaction networks. The results show that t-distributed stochastic neighbor embedding (t-SNE) followed by minimum spanning tree methods groups sparse proteomic data into meaningful clusters more effectively than other methods such as k-means and classical multidimensional scaling. Furthermore, our results show that using a combination of Spearman correlation and Euclidean distance as a dissimilarity representation increases the resolution of clusters. Our analyses show that many clusters contain one or more tyrosine kinases and include known effectors as well as proteins with no known interactions. Visualizing these clusters as networks elucidated previously unknown tyrosine kinase signal transduction pathways that drive cancer. Our approach can be applied to other data types, and can be easily adopted because open source software packages are employed.

Cancer stem cells niche: a target for novel cancer therapeutics

Nowadays, cancer has been a frequent disease, and the first or second most common cause of death worldwide. Despite a better understanding of the biology of cancer cells, the therapy of most cancers has not significantly changed for the past four decades. It is because conventional chemotherapies and/or radiation therapies are usually designed to eradicate highly proliferative cells. Mounting evidence has implicated that cancer is a disease of stem cells. Cancer stem cells (CSC) are often relatively quiescent, and therefore may not be affected by therapies targeting rapidly dividing cells. Like normal stem cells (NSC) residing in a "stem cell niche" that maintains them in a stem-like state, CSC also require a special microenvironment to control their self-renewal and undifferentiated state. The "CSC niche" is likely to be the most crucial target in the treatment of cancer. In this article, we summarize the current knowledge regarding CSC and their niche microenvironments. Understanding of CSC's origin, molecular profile, and interaction with their microenvironments, this could be a paradigm shift in the treatment of cancer, away from targeting the blast cells and towards the targeting of the CSC, thus improving therapeutic outcome.

Translational medicine as a permanent glue and force of clinical medicine and public health: perspectives (1) from 2012 Sino-American symposium on clinical and translational medicine

Abstracts

Health systems globally face challenges and opportunities in balancing quality, access, and cost, where clinical and translational medicine (CTM) should play more important and powerful roles in the identification, development and validation of solutions and strategies. Strategic collaboration can gather global strengths and resources and improve health systems, care delivery, regulations and policies. CTM-driven innovation and development has the potential to achieve step-change improvements across three dimensions. Thus, we have the reasons to believe that CTM will play even more roles in the development of new diagnostics, therapies, healthcare, and policies and SAS-CTM will become more and more important platform to obtain the latest development in CTM internationally and explore new opportunities in the international collaborations.

Perspectives on translational and therapeutic aspects of SIRT1 in inflammaging and senescence

Sirtuin1 (SIRT1), a type III protein deacetylase, is considered as a novel anti-aging protein involved in regulation of cellular senescence/aging and inflammation. SIRT1 level and activity are decreased during lung inflammaging caused by oxidative stress. The mechanism of SIRT1-mediated protection against inflammaging is associated with the regulation of inflammation, premature senescence, telomere attrition, senescence associated secretory phenotype, and DNA damage response. A variety of dietary polyphenols and pharmacological activators are shown to regulate SIRT1 so as to intervene the progression of type 2 diabetes, cancer, cardiovascular diseases, and chronic obstructive pulmonary disease associated with inflammaging. However, recent studies have shown the non-specific regulation of SIRT1 by the aforementioned pharmacological activators and polyphenols. In this perspective, we have briefly discussed the role of SIRT1 in regulation of cellular senescence and its associated secretory phenotype, DNA damage response, particularly in lung inflammaging and during the development of chronic obstructive pulmonary diseases. We have also discussed the potential directions for future translational therapeutic avenues for SIRT1 in modulating lung inflammaging associated with senescence in chronic lung diseases associated with increased oxidative stress.

Targeting Cancer Stem Cells with Nanoparticle-Enabled Therapies

Emerging evidence suggests that multiple tumor types are sustained by a small population of transformed stem-like cells that have the ability to both self-renew and give rise to non-tumorigenic daughter cells that constitute the bulk of a tumor. These cells, which generally constitute a minority of the overall cancer cell population, are highly resistant to conventional therapies and persist following treatment, leading to disease relapse and the formation of distant metastases. Therapies that disrupt the maintenance and survival of cancer stem cells are the subject of active current investigation. This review discusses recent approaches to the application of nanomedicine to the targeting and elimination of cancer stem cells. Specifically, recent publications in the areas of nanoparticle-enabled drug and nucleic acid delivery and photothermal therapy are addressed.