In vitro study to evaluate the effect of granulocyte colony stimulating factor on colorectal adenocarcinoma and on mesenchymal stem cells trans differentiation into cancer stem cells by cancer cells derived exosomes

Background

Colorectal cancer (CRC) is a common and lethal malignancies with poor prognosis. CRC cells release extracellular vesicles called exosomes to facilitate tumor progression by passing bioactive molecules such as proteins and nucleic acids between cells of the tumor and their microenvironment. Granulocyte colony stimulating factor (G-CSF) is a hematopoietic growth factor which mainly affects the lineage of neutrophil and exerts direct anti-tumor effects on various tumor types. The purpose of our study is to investigate the effect of G-CSF on CRC cells and to evaluate its capability to attenuate the potentiality of CRC cells derived exosomes to induce bone marrow-derived mesenchymal stem cells (BM-MSCs) malignant transformation into cancer stem cells (CSCs).

Results

The level of both lncRNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1) (p = 0.014) & β-catenin (p = 0.01) was significantly decreased, whereas programmed cell death 4 (PDCD4) (p = 0.018) was increased in CRC exosomes pre-treated with G-CSF compared to untreated CRC exosomes. Additionally, there was a significant decrease in the cell proliferation in CRC cells pre-treated with G-CSF compared to untreated CRC cells (p = 0.008). Flow cytometric analysis of BM-MSCs showed that G-CSF could attenuate their transformation into CSCs.

Conclusion

G-CSF can be a promising therapeutic agent for CRC treatment.

Photothermal Attenuation of Cancer Cell Stemness, Chemoresistance, and Migration Using CD44-Targeted MoS2 Nanosheets

Cancer stem-like cells (CSCs) play key roles in chemoresistance, tumor metastasis, and clinical relapse. However, current CSC inhibitors lack specificity, efficacy, and applicability to different cancers. Herein, we introduce a nanomaterial-based approach to photothermally induce the differentiation of CSCs, termed "photothermal differentiation", leading to the attenuation of cancer cell stemness, chemoresistance, and metastasis. MoS2 nanosheets and a moderate photothermal treatment were applied to target a CSC surface receptor (i.e., CD44) and modulate its downstream signaling pathway. This treatment forces the more stem-like cancer cells to lose the mesenchymal phenotype and adopt an epithelial, less stem-like state, which shows attenuated self-renewal capacity, more response to anticancer drugs, and less invasiveness. This approach could be applicable to various cancers due to the broad availability of the CD44 biomarker. The concept of using photothermal nanomaterials to regulate specific cellular activities driving the differentiation of CSCs offers a new avenue for treating refractory cancers.

PPARβ/δ Ligands Regulate Oxidative Status and Inflammatory Response in Inflamed Corpus Luteum-An In Vitro Study

Inflammation in the female reproductive system causes serious health problems including infertility. The aim of this study was to determine the in vitro effects of peroxisome proliferator-activated receptor-beta/delta (PPARβ/δ) ligands on the transcriptomic profile of the lipopolysaccharide (LPS)-stimulated pig corpus luteum (CL) in the mid-luteal phase of the estrous cycle using RNA-seq technology. The CL slices were incubated in the presence of LPS or in combination with LPS and the PPARβ/δ agonist-GW0724 (1 μmol/L or 10 μmol/L) or the antagonist-GSK3787 (25 μmol/L). We identified 117 differentially expressed genes after treatment with LPS; 102 and 97 differentially expressed genes after treatment, respectively, with the PPARβ/δ agonist at a concentration of 1 μmol/L or 10 μmol/L, as well as 88 after the treatment with the PPARβ/δ antagonist. In addition, biochemical analyses of oxidative status were performed (total antioxidant capacity and activity of peroxidase, catalase, superoxide dismutase, and glutathione S-transferase). This study revealed that PPARβ/δ agonists regulate genes involved in the inflammatory response in a dose-dependent manner. The results indicate that the lower dose of GW0724 showed an anti-inflammatory character, while the higher dose seems to be pro-inflammatory. We propose that GW0724 should be considered for further research to alleviate chronic inflammation (at the lower dose) or to support the natural immune response against pathogens (at the higher dose) in the inflamed corpus luteum.

Electrostatic potential difference between tumor and paratumor regulates cancer stem cell behavior and prognose tumor spread

Tumor spread is responsible for most deaths related to cancer. Increasing the accuracy of cancer prognosis is critical to reducing the high mortality rates in cancer patients. Here, we report that the electrostatic potential difference (EPD) between tumor and its paratumor tissue is a prognostic marker for tumor spread. This finding is concluded from the patient-specific EPD values and clinical observation. The electrostatic potential values were measured on tissue cryosections from 51 patients using Kelvin probe force microscopy (KPFM). A total of ~44% (15/34) patients of Vtumor-paratumor > 0 were featured with tumor spread, whereas only ~18% (2/11) patients of Vtumor-paratumor < 0 had tumor spread. Next, we found the increased enrichment of cancer stem cells in paratumors with lower electrostatic potentials using immunofluorescence imaging, which suggested the attribution of tumor spread to the galvanotaxis of cancer stem cells (CSCs) toward lower potential. The findings were finally validated in breast and lung spheroid models composed of differentiated cancer cells and cancer stem cells at the ratio of 1:1 and embedded in Matrigel dopped with negative-, neutral- and positive-charged polymers and CSCs prefer to spread out of spheroids to lower electrostatic potential sites. This work may inspire the development of diagnostic and prognostic strategies targeting at tissue EPDs and CSCs for tumor therapy.

Molecular Subtypes of Head and Neck Cancer in Patients of African Ancestry

PURPOSE

The purpose of this study was to better understand the complex molecular biomarkers and signatures of head and neck cancer (HNC) among Black patients and identify possible molecular changes associated with HNC disparities.

EXPERIMENTAL DESIGN

Molecular subtypes and genomic changes in HNC samples from patients of African and European ancestry in The Cancer Genome Atlas, Memorial Sloan Kettering Cancer Center, Broad Institute, MD Anderson Cancer Center, and John Hopkins University were identified. Molecular features (genomic, proteomic, transcriptomic) associated with race and genomic alterations associated with clinical outcomes were determined. An independent cohort of HNC tumor specimens was used to validate the primary findings using IHC.

RESULTS

Black patients were found to have a younger age at diagnosis, more aggressive tumor types, higher rates of metastasis, and worse survival compared with White patients. Black patients had fewer human papillomavirus-positive tumor types and higher frequencies of laryngeal subtype tumors. Higher frequencies of TP53, MYO18B, KMT2D, and UNC13C mutations and a lower frequency of PIK3CA mutations were observed in Black patients. Tumors of Black patients showed significant enrichment of c-MYC and RET-tyrosine signaling and amplifications. A significant increase in tumor expression of c-MYC in Black patients was observed and was associated with poor survival outcomes in the independent cohort.

CONCLUSIONS

Novel genomic modifications and molecular signatures may be related to environmental, social, and behavioral factors associated with racial disparities in HNC. Unique tumor mutations and biological pathways have potential clinical utility in providing more targeted and individualized screening, diagnostic, and treatment modalities to improve health outcomes.

Complementary and Integrative Medicine in Pancreatic Cancer

PURPOSE OF REVIEW

Pancreatic cancer has high mortality and morbidity rates, associated with the issues of typically late diagnosis and the limited effectiveness of current treatments. Patients tend to experience multiple symptoms that can include anxiety, fear, depression, fatigue, weakness, peripheral neuropathy, and abdominal pain, which reduce quality of life (QoL) and may compromise the treatment continuum. Many of those symptoms are amenable to complementary and integrative medicine (CIM) therapies as a part of supportive and palliative care. This article reviews research findings on the beneficial effect of use of CIM modalities in regard to pancreatic cancer, with emphasis on pancreatic ductal adenocarcinoma (PDAC).

RECENT FINDINGS

Given the often-poor prognosis of the disease, patients with PDAC often seek integrative therapies to help manage the disease itself, to provide support through cancer treatment and its symptoms, and to provide emotional stress relief. Data is accumulating in the past few years on the potential benefits of CIM to the management of pancreatic cancer symptoms and treatment side effects, in order to augment supportive care. This data reveal that nutrition counselling; digestive enzyme therapy; microbiome support; dietary supplements; lifestyle interventions (physical activity and circadian health/sleep hygiene) appear to improve QoL of these patients through reduced symptom burden and meeting psychological needs, such as distress and fatigue. Acupuncture, mindfulness, yoga, reflexology, massage, and homeopathy may also contribute to symptom reduction, both physical and psychological, in all stages of the disease. There is supporting evidence that some CIM modalities may alleviate side effects and symptoms related to pancreatic cancer and its treatment, suggesting that practitioners might consider integrating these modalities in certain situations encountered in the treatment of pancreatic cancer. Further investigation is needed to define the optimal integration of CIM into the treatment and supportive care of patients affected by pancreatic cancer.

In silico designing and expression of novel recombinant construct containing the variable part of CD44 extracellular domain for prediagnostic breast cancer

BACKGROUND

CD44, as a tumor-associated marker, can be used to detect stem cells in breast cancer. While CD44 is expressed in normal epithelial cells, carcinoma cells overexpress CD44.

AIMS

In the current study, we designed a recombinant protein that included the variable component of the CD44 (CD44v) extracellular domain to apply in clinical diagnosis of breast cancer.

METHODS

A total of 100 CD44v amino-acid residues were determined, and the structure was examined using bioinformatics tools. The construct was inserted into the PET28a vector and transformed in E. coli BL21(DE3). A nearly 12 kDa fusion protein was obtained by Ni-NTA affinity metal chromatography. Recombinant CD44v was examined by Western blotting, ELISA, and immunohistochemistry (IHC) assays.

RESULTS

The findings revealed that the structure of rCD44v was stable, and its antigenic domain was exposed. The recombinant CD44v was confirmed by western blotting, and the presence of antibodies against recombinant CD44v protein in the patient's serum was detected by the ELISA. Our data demonstrated a link between CD44v serum levels and the prevalence of breast cancer.

CONCLUSION

Assessments of antiCD44v antibodies with rCD44v could be a useful tool for identifying breast cancer in its early stages, which can lead to better outcomes.

Heterogeneous population of macrophages in the development of non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is characterized by a spectrum of hepatic diseases, including fatty liver, non-alcoholic steatohepatitis, cirrhosis, and hepatocellular carcinoma. NAFLD is a hepatic manifestation of metabolic syndrome and has become the leading cause of liver transplantation, necessitating an in-depth understanding of its underlying pathogenic mechanisms and the identification of viable drug targets. Although fatty liver is benign and does not exert marked liver damage or inflammation, NAFLD progression involves inflammatory processes facilitated by immune cells. Macrophages and monocytes constitute the pool of innate immune cells that contribute to NAFLD development in association with other cell types, such as neutrophils, T cells, and natural killer cells. The concept that macrophages contribute to the inflammatory processes in NAFLD development has long been debated; however, the remarkable advances in experimental techniques have rapidly uncovered new subpopulations of macrophages and monocytes, whose functions need to be comprehensively elucidated. The current review focuses on the recent expansion of our knowledge of the heterogeneous population of macrophages crucially involved in NAFLD development. In addition, the present paper discusses ongoing efforts to target macrophages and inflammatory processes to develop optimal therapeutic agents against non-alcoholic steatohepatitis.

Synergistic effects of PI3K inhibition and pioglitazone against acute promyelocytic leukemia cells

BACKGROUND

Although pioglitazone, a well-known anti-diabetic agent, has recently established itself as a pillar of cancer treatment, its therapeutic value could be attenuated by the aberrant activation of the PI3K/Akt pathway.

AIM

To evaluate whether the PI3K/Akt suppression in leukemic cells could potentiate the anti-leukemic effects of pioglitazone.

METHODS

To assess the anti-leukemic effects of PI3K/Akt inhibitors on anti-leukemic effects of pioglitazone, we used MTT and trypan blue assays. Flow cytometric analysis and qRT-PCR were also applied to evaluate cell cycle and apoptosis.

RESULT

The resulting data revealed that upon PPARγ stimulation in different leukemic cell lines using pioglitazone, the survival and the proliferative capacity of the cells were significantly halted. Then, we evaluated the impact of the PI3K/Akt axis on the effectiveness of the drug in the most sensitive leukemic cell line; NB4 cells. Our results showed that treatment of NB4 cells with the PI3K inhibitors increased the sensitivity of leukemic cells to pioglitazone to the degree that even lower concentrations of the agent succeeded to induce apoptotic as well as the anti-proliferative effects. Moreover, it seems that PI3K inhibition could potentiate the anti-leukemic effect of pioglitazone through induction of p21-mediated sub-G1 cell cycle arrest and altering the balance between the pro-and anti-apoptotic genes.

CONCLUSION

This study sheds light on the significance of the PI3K/Akt pathway in APL cell sensitivity to pioglitazone and proposed that the presence of the PI3K inhibitor in the therapeutic regimen containing pioglitazone could be promising in the treatment of this malignancy.

Osteogenic and Adipogenic Differentiation Potential of Oral Cancer Stem Cells May Offer New Treatment Modalities

(1) Treatment failure of oral squamous cell carcinoma (OSCC) is generally due to the development of therapeutic resistance caused by the existence of cancer stem cells (CSCs), a small cell subpopulation with marked self-renewal and differentiation capacity. Micro RNAs, notably miRNA-21, appear to play an important role in OSCC carcinogenesis. Our objectives were to explore the multipotency of oral CSCs by estimating their differentiation capacity and assessing the effects of differentiation on stemness, apoptosis, and several miRNAs' expression. (2) A commercially available OSCC cell line (SCC25) and five primary OSCC cultures generated from tumor tissues obtained from five OSCC patients were used in the experiments. Cells harboring CD44, a CSC marker, were magnetically separated from the heterogeneous tumor cell populations. The CD44⁺ cells were then subjected to osteogenic and adipogenic induction, and the specific staining was used for differentiation confirmation. The kinetics of the differentiation process was evaluated by qPCR analysis of osteogenic (Bone Morphogenetic Protein-BMP4, Runt-related Transcription Factor 2-RUNX2, Alkaline Phosphatase-ALP) and adipogenic (Fibroblast Activation Protein Alpha-FAP, LIPIN, Peroxisome Proliferator-activated Receptor Gamma-PPARG) markers on days 0, 7, 14, and 21. Embryonic markers (Octamer-binding Transcription Factor 4-OCT4, Sex Determining Region Y Box 2-SOX2, and NANOG) and micro RNAs (miRNA-21, miRNA-133, and miRNA-491) were also correspondingly evaluated by qPCR. An Annexin V assay was used to assess the potential cytotoxic effects of the differentiation process. (3) Following differentiation, the levels of markers for the osteo/adipo lineages showed a gradual increase from day 0 to day 21 in the CD44⁺ cultures, while stemness markers and cell viability decreased. The oncogenic miRNA-21 also followed the same pattern of gradual decrease along the differentiation process, while tumor suppressor miRNA-133 and miRNA-491 levels increased. (4) Following induction, the CSCs acquired the characteristics of the differentiated cells. This was accompanied by loss of stemness properties, a decrease of the oncogenic and concomitant, and an increase of tumor suppressor micro RNAs.

Periplocin Overcomes Bortezomib Resistance by Suppressing the Growth and Down-Regulation of Cell Adhesion Molecules in Multiple Myeloma

Multiple myeloma (MM) is an incurable hematological malignant disorder of bone marrow. Patients with MM receive multiple lines of chemotherapeutic treatments which often develop bortezomib (BTZ) resistance and relapse. Therefore, it is crucial to identify an anti-MM agent to overcome the BTZ resistance of MM. In this study, we screened a library of 2370 compounds against MM wild-type (ARP1) and BTZ-resistant type (ARP1-BR) cell lines and found that periplocin (PP) was the most significant anti-MM natural compound. We further investigated the anti-MM effect of PP by using annexin V assay, clonogenic assays, aldefluor assay, and transwell assay. Furthermore, RNA sequencing (RNA-seq) was performed to predict the molecular effects of PP in MM followed by verification through qRT-PCR and Western blot analysis. Moreover, ARP1 and ARP1-BR xenograft mice models of MM were established to confirm the anti-MM effects of PP invivo. The results showed that PP significantly induced apoptosis, inhibited proliferation, suppressed stemness, and reduced the cell migration of MM. The expression of cell adhesion molecules (CAMs) was suppressed upon PP treatment in vitro and in vivo. Overall, our data recommend PP as an anti-MM natural compound with the potential to overcome BTZ resistance and downregulate CAMs in MM.

Preclinical and Clinical Trials of New Treatment Strategies Targeting Cancer Stem Cells in Subtypes of Breast Cancer

Breast cancer (BC) can be classified into various histological subtypes, each associated with different prognoses and treatment options, including surgery, radiation, chemotherapy, and endocrine therapy. Despite advances in this area, many patients still face treatment failure, the risk of metastasis, and disease recurrence, which can ultimately lead to death. Mammary tumors, like other solid tumors, contain a population of small cells known as cancer stem-like cells (CSCs) that have high tumorigenic potential and are involved in cancer initiation, progression, metastasis, tumor recurrence, and resistance to therapy. Therefore, designing therapies specifically targeting at CSCs could help to control the growth of this cell population, leading to increased survival rates for BC patients. In this review, we discuss the characteristics of CSCs, their surface biomarkers, and the active signaling pathways associated with the acquisition of stemness in BC. We also cover preclinical and clinical studies that focus on evaluating new therapy systems targeted at CSCs in BC through various combinations of treatments, targeted delivery systems, and potential new drugs that inhibit the properties that allow these cells to survive and proliferate.

The role of peroxisome proliferator-activated receptors in the modulation of hyperinflammation induced by SARS-CoV-2 infection: A perspective for COVID-19 therapy

Coronavirus disease 2019 (COVID-19) is a severe respiratory disease caused by infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that affects the lower and upper respiratory tract in humans. SARS-CoV-2 infection is associated with the induction of a cascade of uncontrolled inflammatory responses in the host, ultimately leading to hyperinflammation or cytokine storm. Indeed, cytokine storm is a hallmark of SARS-CoV-2 immunopathogenesis, directly related to the severity of the disease and mortality in COVID-19 patients. Considering the lack of any definitive treatment for COVID-19, targeting key inflammatory factors to regulate the inflammatory response in COVID-19 patients could be a fundamental step to developing effective therapeutic strategies against SARS-CoV-2 infection. Currently, in addition to well-defined metabolic actions, especially lipid metabolism and glucose utilization, there is growing evidence of a central role of the ligand-dependent nuclear receptors and peroxisome proliferator-activated receptors (PPARs) including PPARα, PPARβ/δ, and PPARγ in the control of inflammatory signals in various human inflammatory diseases. This makes them attractive targets for developing therapeutic approaches to control/suppress the hyperinflammatory response in patients with severe COVID-19. In this review, we (1) investigate the anti-inflammatory mechanisms mediated by PPARs and their ligands during SARS-CoV-2 infection, and (2) on the basis of the recent literature, highlight the importance of PPAR subtypes for the development of promising therapeutic approaches against the cytokine storm in severe COVID-19 patients.

Development of a Novel Anti-CD44 Variant 6 Monoclonal Antibody C44Mab-9 for Multiple Applications against Colorectal Carcinomas

CD44 is a cell surface glycoprotein, and its isoforms are produced by the alternative splicing with the standard and variant exons. The CD44 variant exon-containing isoforms (CD44v) are overexpressed in carcinomas. CD44v6 is one of the CD44v, and its overexpression predicts poor prognosis in colorectal cancer (CRC) patients. CD44v6 plays critical roles in CRC adhesion, proliferation, stemness, invasiveness, and chemoresistance. Therefore, CD44v6 is a promising target for cancer diagnosis and therapy for CRC. In this study, we established anti-CD44 monoclonal antibodies (mAbs) by immunizing mice with CD44v3-10-overexpressed Chinese hamster ovary (CHO)-K1 cells. We then characterized them using enzyme-linked immunosorbent assay, flow cytometry, western blotting, and immunohistochemistry. One of the established clones (C₄₄Mab-9; IgG₁, kappa) reacted with a peptide of the variant 6-encoded region, indicating that C₄₄Mab-9 recognizes CD44v6. Furthermore, C₄₄Mab-9 reacted with CHO/CD44v3-10 cells or CRC cell lines (COLO201 and COLO205) by flow cytometry. The apparent dissociation constant (K_D) of C₄₄Mab-9 for CHO/CD44v3-10, COLO201, and COLO205 was 8.1 × 10^-9 M, 1.7 × 10^-8 M, and 2.3 × 10^-8 M, respectively. C₄₄Mab-9 detected the CD44v3-10 in western blotting, and partially stained the formalin-fixed paraffin-embedded CRC tissues in immunohistochemistry. Collectively, C₄₄Mab-9 is useful for detecting CD44v6 in various applications.

Hexafluoropropylene oxide trimer acid (HFPO-TA) disturbs embryonic liver and biliary system development in zebrafish

Hexafluoropropylene oxide trimer acid (HFPO-TA), a novel alternative to perfluorooctanoic acid (PFOA), has emerged as a potential environmental pollutant. Here, to investigate the toxic effects of HFPO-TA on liver and biliary system development, zebrafish embryos were exposed to 0, 50, 100, or 200 mg/L HFPO-TA from 6 to 120 h post-fertilization (hpf). Results showed that the 50 % lethal concentration (LC₅₀) of HFPO-TA was 231 mg/L at 120 hpf, lower than that of PFOA. HFPO-TA exposure decreased embryonic hatching, survival, and body length. Furthermore, HFPO-TA exerted higher toxicity at the specification stage than during the differentiation and maturation stages, leading to small-sized livers in Tg(fabp10a: DsRed) transgenic larvae and histopathological changes. Significant decreases in the mRNA expression of genes related to liver formation were observed. Alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TBIL), and direct bilirubin (DBIL) levels were significantly increased. HFPO-TA decreased total cholesterol (TCHO) and triglyceride (TG) activities, disturbed lipid metabolism through the peroxisome proliferator-activated receptor (PPAR) pathway, and induced an inflammatory response. Furthermore, HFPO-TA inhibited intrahepatic biliary development in Tg(Tp1:eGFP) transgenic larvae and interfered with transcription of genes associated with biliary duct development. HFPO-TA reduced bile acid synthesis but increased bile acid transport, resulting in disruption of bile acid metabolism. Therefore, HFPO-TA influenced embryonic liver and biliary system morphogenesis, caused liver injury, and may be an unsafe alternative for PFOA.

The hypoxia-inducible factor-1α in stemness and resistance to chemotherapy in gastric cancer: Future directions for therapeutic targeting

Hypoxia-inducible factor-1α (HIF-1α) is a crucial mediator of intra-tumoral heterogeneity, tumor progression, and unresponsiveness to therapy in tumors with hypoxia. Gastric tumors, one of the most aggressive tumors in the clinic, are highly enriched in hypoxic niches, and the degree of hypoxia is strongly correlated with poor survival in gastric cancer patients. Stemness and chemoresistance in gastric cancer are the two root causes of poor patient outcomes. Based on the pivotal role of HIF-1α in stemness and chemoresistance in gastric cancer, the interest in identifying critical molecular targets and strategies for surpassing the action of HIF-1α is expanding. Despite that, the understanding of HIF-1α induced signaling in gastric cancer is far from complete, and the development of efficacious HIF-1α inhibitors bears various challenges. Hence, here we review the molecular mechanisms by which HIF-1α signaling stimulates stemness and chemoresistance in gastric cancer, with the clinical efforts and challenges to translate anti-HIF-1α strategies into the clinic.

Antibody Drug Conjugates of Near-Infrared Photoimmunotherapy (NIR-PIT) in Breast Cancers

Worldwide, the incidence rate of breast cancer is the highest in women. Approximately 2.3 million people were newly diagnosed and 0.685 million were dead of breast cancer in 2020, which continues to grow. Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype with a higher risk of recurrence and metastasis, but disappointly, there are no effective and specific therapies clinically, especially for patients presenting with metastatic diseases. Therefore, it is urgent to develop a new type of cancer therapy for survival improvisation and adverse effects alleviation of breast cancers. Near-infrared photoimmunotherapy (NIR-PIT) is a newly developed, photochemistry-based cancer therapy. It was drive by an antibody-photoabsorber conjugate (APC) which is triggered by near-infrared light. The key part of APC is a cancer-targeting monoclonal antibody (mAb) that can bind to receptors or antigens on the surface of tumor cells. Because of this targeted conjugate accumulation, subsequent deployment of focal NIR-light results in functional damage on the targeted cell membranes without harming the immediately adjacent receptor-negative cells and evokes a kind of photochemical, speedy, and highly specific immunogenic cell death (ICD) of cancer cells with corresponding antigens. Subsequently, immature dendritic cells adjacent to dying cancer cells will become mature, further inducing a host-oriented anti-cancer immune response, complicatedly and comprehensively. Currently, NIR-PIT has progressed into phase 3 clinical trial for recurrent head and neck cancer. And preclinical studies have illustrated strong therapeutic efficacy of NIR-PIT targeting various molecular receptors overexpressed in breast cancer cells, including EGFR, HER2, CD44c, CD206, ICAM-1 and FAP-α. Thereby, NIR-PIT is in early trials, but appears to be a promising breast cancer therapy and moving into the future. Here, we present the specific advantages and discuss the most recent preclinical studies against several transmembrane proteins of NIR-PIT in breast cancers.

Thioalbamide inhibits FoF1-ATPase in breast cancer cells and reduces tumor proliferation and invasiveness in breast cancer in vivo models

OBJECTIVE

Thioalbamide is a ribosomally synthesized and post-translationally modified peptide (RiPP) belonging to the family of thioamitides, a rare class of microbial specialized metabolites with unusual post-translational modifications and promising biological activities. Recent studies have demonstrated the ability of thioalbamide to exert highly selective cytotoxic effects on tumor cells by affecting their energy metabolism, thus causing abnormal ROS production and triggering apoptosis. This study is aimed to investigate the molecular mechanisms underlying the antitumor activity of thioalbamide in order to identify its exact molecular target.

METHODS

Wild type MCF-7 and MDA-MB-231 breast cancer cell lines as well as cancer cells deprived of mitochondrial DNA (ρ⁰ cells) were employed in order to assess thioalbamide effects on tumor bioenergetics. In this regard, metabolic profile was evaluated by a Seahorse XFe96 analyzer, and the activity of the enzyme complexes involved in oxidative phosphorylation was quantified by spectrophotometric assays. Thioalbamide effects on tumor invasiveness were assessed by gelatin zymography experiments and invasion assays. In vivo experiments were carried out on breast cancer xenograft and "experimental metastasis" mouse models.

RESULTS

Experiments carried out on ρ⁰ breast cancer cells, together with Seahorse analysis and the application of spectrophotometric enzymatic assays, highlighted the ability of thioalbamide to affect the mitochondrial respiration process, and allowed to propose the F_oF₁-ATPase complex as its main molecular target in breast cancer cells. Additionally, thioalbamide-mediated OXPHOS inhibition was shown, for the first time, to reduce tumor invasiveness by inhibiting metalloproteinase-9 secretion. Furthermore, this study has confirmed the antitumor potential of thioalbamide in two different in vivo models. In particular, experiments on MCF-7 and MDA-MB-231 xenograft mouse models have confirmed in vivo its high anti-proliferative and pro-apoptotic activity, while experiments on MDA-MB-231 ″experimental metastasis" mouse models have highlighted its ability to inhibit breast cancer cell invasiveness.

CONCLUSIONS

Overall, our results shed more light on the molecular mechanisms underlying the pharmacological potential of thioamidated peptides, thus reducing the gap that separates this rare class of microbial metabolites from clinical studies, which could validate them as effective tools for cancer treatment.

Role of epigenetics in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive cancers, associated with poor survival outcomes. Lack of early diagnosis, resistance to conventional therapeutic treatments (including immunotherapy) and recurrence are some of the major hurdles in PDAC and contribute to its poor survival rate. While the risk of genetic predisposition to cancers is widely acknowledged and understood, recent advances in whole-genome and next-generation sequencing techniques have led to the acknowledgment of the role played by epigenetics, especially in PDAC. Epigenetic changes are heritable genetic modifications that influence gene expression without altering the DNA sequence. Epigenetic mechanisms (e.g., DNA methylation, post-translational modification of histone complexes and ncRNA) that result in reversible changes in gene expression are increasingly understood to be responsible for tumor initiation, development and even escape from immune surveillance. Our review seeks to highlight the various components of the epigenetic machinery that are known to be implicated in PDAC initiation and development and the feasibility of targeting these components to identify novel pharmacological strategies that could potentially lead to breakthroughs in PDAC treatment.

Targeting Cancer Stem Cells as the Key Driver of Carcinogenesis and Therapeutic Resistance

The emerging concept of cancer stem cells (CSCs) as the key driver behind carcinogenesis, progression, and diversity has displaced the prior model of a tumor composed of cells with similar subsequently acquired mutations and an equivalent capacity for renewal, invasion, and metastasis. This significant change has shifted the research focus toward targeting CSCs to eradicate cancer. CSCs may be characterized using cell surface markers. They are defined by their capacity to self-renew and differentiate, resist conventional therapies, and generate new tumors following repeated transplantation in xenografted mice. CSCs' functional capabilities are governed by various intracellular and extracellular variables such as pluripotency-related transcription factors, internal signaling pathways, and external stimuli. Numerous natural compounds and synthetic chemicals have been investigated for their ability to disrupt these regulatory components and inhibit stemness and terminal differentiation in CSCs, hence achieving clinical implications. However, no cancer treatment focuses on the biological consequences of these drugs on CSCs, and their functions have been established. This article provides a biomedical discussion of cancer at the time along with an overview of CSCs and their origin, features, characterization, isolation techniques, signaling pathways, and novel targeted therapeutic approaches. Additionally, we highlighted the factors endorsed as controlling or helping to promote stemness in CSCs. Our objective was to encourage future studies on these prospective treatments to develop a framework for their application as single or combined therapeutics to eradicate various forms of cancer.

PD-L1 is highly expressed in ovarian cancer and associated with cancer stem cells populations expressing CD44 and other stem cell markers

BACKGROUND

Immune checkpoint inhibitors, including PD-L1 (programmed death ligand-1) inhibitors have well documented anticancer therapeutic effect in most types of cancers but its use in the treatment of ovarian cancer is not yet proven. The aim of our study is to explore the predictive biomarkers in ovarian cancer and its association with the outcomes. We have investigated the role of PD-L1 expressions in the tumor microenvironment cells including immune cells and cancer stem cells in different types of ovarian cancer.

METHODS

A total of 119 surgical archived ovarian cancer samples were collected from the pathology department at King Fahad Specialist Hospital, Dammam, Saudi Arabia that included serous carcinomas, clear cell carcinomas, mucinous carcinomas, endometrioid carcinomas, and granulosa cell tumors. Immunohistochemistry (IHC) staining was performed using (i) PD-L1 antibodies to detect PD-L1 expressions; (ii) CD8 and CD4 to detect Tumor Infiltrating Lymphocytes (TILs); and (iii) CD44, LGR5, and ALDH2 to detect stem cell markers. The clinicopathological data were collected from patients' medical record to investigate the association with PD-L1, TILs, and stem cells expressions.

RESULTS

We report high PD-L1 expressions in 47.8% of ovarian cancer samples. PD-L1 expressions were detected in different types of epithelial ovarian cancer and were not associated with poor prognosis of ovarian cancer. However, determining the expression levels of TILs in the ovarian cancer tissues found that 81% (n = 97) of ovarian cancer samples have TILs that express both of CD8 and CD4 and significantly associated with high PD-L1 expressions. Interestingly, we have found that ovarian cancer tissues with high expressions of PD-L1 were associated with high expressions of stem cells expressing CD44 and LGR5.

CONCLUSIONS

PD-L1 is highly expressed in the serous type of ovarian carcinomas and the overall expression of PD-L1 is not associated with poor survival rate. Furthermore, PD-L1 expressions are strongly associated with TILs and stem cell markers in ovarian cancer. Inhibiting the PD-L1 using immune checkpoint inhibitors might downregulate stem cell population that known to be associated with cancer recurrence.

Risk Assessment and Pancreatic Cancer: Diagnostic Management and Artificial Intelligence

Pancreatic cancer (PC) is one of the deadliest cancers, and it is responsible for a number of deaths almost equal to its incidence. The high mortality rate is correlated with several explanations; the main one is the late disease stage at which the majority of patients are diagnosed. Since surgical resection has been recognised as the only curative treatment, a PC diagnosis at the initial stage is believed the main tool to improve survival. Therefore, patient stratification according to familial and genetic risk and the creation of screening protocol by using minimally invasive diagnostic tools would be appropriate. Pancreatic cystic neoplasms (PCNs) are subsets of lesions which deserve special management to avoid overtreatment. The current PC screening programs are based on the annual employment of magnetic resonance imaging with cholangiopancreatography sequences (MR/MRCP) and/or endoscopic ultrasonography (EUS). For patients unfit for MRI, computed tomography (CT) could be proposed, although CT results in lower detection rates, compared to MRI, for small lesions. The actual major limit is the incapacity to detect and characterize the pancreatic intraepithelial neoplasia (PanIN) by EUS and MR/MRCP. The possibility of utilizing artificial intelligence models to evaluate higher-risk patients could favour the diagnosis of these entities, although more data are needed to support the real utility of these applications in the field of screening. For these motives, it would be appropriate to realize screening programs in research settings.

Involvement of angiogenesis in cancer-associated acinar-to-ductal metaplasia lesion of pancreatic cancer invasive front

PURPOSE

This study aimed to demonstrate the involvement of angiogenesis in cancer-associated acinar-to-ductal metaplasia (CA-ADM) lesion of invasive front pancreatic ductal adenocarcinoma (PDAC) and investigate the possible mechanism.

METHODS

Tissue samples from 128 patients with PDAC and 36 LSL-Kras^G12D/+; LSL-Trp53^R172H/+; Pdx-1-Cre mice were analyzed. Immunohistochemical assay was performed using HE, anti-CK19 and anti-amylase to confirm the presence of CA-ADM lesions, using anti-CD34 and anti-CD31 to measure microvessel density (MVD), and using anti-CD68, anti-CD163, anti-iNOS, or anti-MMP9 to evaluate the immune microenvironment. We performed multiplex immunohistochemical assay to detect the co-expression of MMP9 and CD68 on macrophage. We examined clinical outcomes and other clinicopathological factors to determine the significance of high-level MVD of CA-ADM on survival and liver metastasis. We performed tube formation assay to evaluate the effect of macrophage on angiogenic capacity in vitro.

RESULTS

Angiogenesis was significantly abundant in CA-ADM lesions compared with that in PDAC lesions in human and mouse tissues. High-level MVD in CA-ADM lesions was an independent predictor of poor prognosis (P = 0.0047) and the recurrence of liver metastasis (P = 0.0027). More CD68-positive and CD163-positive macrophages were detected in CA-ADM lesions than in PDAC. The percentage of CD68-positive macrophages was positively correlated with MVD in CA-ADM lesions. Multiplex-immunostaining revealed that MMP9 was expressed in CD68-positive macrophages of CA-ADM lesions. In CA-ADM lesions, the percentage of macrophages was positively correlated with MMP9 expression, which positively correlated with microvessel density.

CONCLUSION

CA-ADM related angiogenesis is a promising predictive marker for poor prognosis of PDAC and may provide an attractive therapeutic target for PDAC.

Scintillation Proximity Assay (SPA)-Based Radioligand Binding for PPARα, PPARγ, and PPARδ Receptors

Peroxisome proliferator-activated receptors (PPARs) have been exploited as drug targets for combating multiple diseases. Several activators with different selectivity for the PPAR α, γ, and δ subtypes have been introduced into the market or have reached advanced clinical trials. Binding assays are of utmost importance for the discovery and profiling of such PPAR ligands. Binding assays are often based on radioligands, in particular, tritiated molecules are applied. We developed synthetic procedures for tritiating various PPAR agonists and applied these radioligands for setting up a scintillation proximity assay (SPA) for PPAR α, γ, and δ. These SPAs allow to assess the binding affinities of PPAR α, γ, and δ ligands, along with their respective subtype selectivity profiles. Therefore, SPA is an important tool for hit discovery and lead optimization campaigns aimed at identifying next-generation PPAR ligands.

[Relationship between PD-L1 expression and tumor stem cell marker CD44 as a promising basis for the development of new approaches to cancer targeted therapy]

Immunotherapy of malignant tumors is a rapidly developing area of oncology. PD-1 is a receptor expressed by activated T-lymphocytes. As a result of its interaction with the ligand (PD-L1 or PD-L2), the activity of T-lymphocytes is inhibited and their apoptosis occurs. Drugs that inhibit the interaction of PD-1 with ligands have an immunostimulatory effect and are effective in the treatment of many types of neoplasms: melanoma, lung cancer, bladder cancer, stomach cancer, various lymphomas, etc. However, response to this treatment is observed only in a narrow cohort of patients. To increase the effectiveness of immunotherapy, combined preparations and nanoparticles are being developed and created to enhance the effect of PD-L1 inhibitors, and containing hyaluronic acid as a ligand for the CD44 protein, which is expressed in many human tumors. However, the issue of co-expression of CD44 and PD-L1 remains poorly understood. This review is devoted to describing the features of co-expression and the mechanisms of interaction between CD44 and PD-L1. Promising directions for the development of new approaches to the immunotherapy of malignant tumors are presented.

Tumor lysis syndrome promotes cancer chemoresistance and relapse through AMPK inhibition

Cancer is a disease caused when cells divide uncontrollably and spread into surrounding tissues. There are different therapeutic modalities that control cancer growth, of which surgery, chemotherapy, and radiotherapy. Chemotherapy is a cancer treatment approach in which medications are used to inhibit cell proliferation and tumor multiplication, thus avoiding invasion and metastasis and thus eradicate cancer. One of the common complications associated with cancer chemotherapy is rapid lysis of expanding tumor cells, known as tumor lysis syndrome (TLS). TLS is associated with number of metabolic changes such as hyperuricemia, hyperkalemia, hyperphosphatemia and hypocalcemia. Among the consequences of hyperuricemia, hyperkalemia, hyperphosphatemia and hypocalcemia is the inhibition of 5' AMP-activated protein kinase (AMPK). Inhibition of AMPK induced different cancer chemo-resistance mechanisms such as cancer stem cells (CSCs), p-glycoproteins, Octamer-binding transcription factor 4 (OCT-4), homeobox protein NANOG, Krüppel-like factor 4 (KLF4) and immune microenvironment and thus leads to poor response to chemotherapy and even relapses after treatment. Our review aims to uncover new mechanisms underlying the metabolic consequences of tumor lysis on AMPK in tumor microenvironment. In this review, we also investigated the effect of AMPK on different cancer chemo-resistance mechanisms such as cancer stem cells, p-glycoproteins, OCT-4, NANOG, KLF4 and immune microenvironment.

Protein-Metabolite Interactions Shape Cellular Metabolism and Physiology

Protein-metabolite interactions regulate many important cellular processes but still remain understudied. Recent technological advancements are gradually uncovering the complexity of the protein-metabolite interactome. Here, we highlight some classic and recent examples of how protein metabolite interactions regulate metabolism, both locally and globally, and how this contributes to cellular physiology. We also discuss the importance of these interactions in diseases such as cancer.

Glucagon-like peptide-1 receptor regulates receptor of advanced glycation end products in high glucose-treated rat mesangial cells

BACKGROUND

Hyperglycemia-induced advanced glycation end products (AGEs) and receptor for AGEs (RAGEs) play major roles in diabetic nephropathy progression. In previous study, both glucagon-like peptide-1 (GLP-1) and peroxisome proliferator-activated receptors delta (PPARδ) agonists were shown to have anti-inflammatory effect on AGE-treated rat mesangial cells (RMCs). The interaction among PPARδ agonists, GLP-1, and AGE-RAGE axis is, however, still unclear.

METHODS

In this study, the individual and synergic effect of PPARδ agonist (L-165 041) and siRNA of GLP-1 receptor (GLP-1R) on the expression of GLP-1, GLP-1R, RAGE, and cell viability in AGE-treated RMCs were investigated.

RESULTS

L-165 041 enhanced GLP-1R mRNA and protein expression only in the presence of AGE. The expression of RAGE mRNA and protein was enhanced by AGE, attenuated by L-165 041, and siRNA of GLP-1R reversed L-165 041-induced inhibition. Cell viability was also inhibited by AGE. L-165 041 attenuated AGE-induced inhibition and siRNA GLP-1R diminished L-165 041 effect.

CONCLUSION

PPARδ agonists increase GLP-1R expression on RMC in the presence of AGE. PPARδ agonists also attenuate AGE-induced upregulated RAGE expression and downregulated cell viability. The effect of PPARδ agonists needs the cooperation of GLP-1R activation.

CD44v3 is a marker of invasive cancer stem cells driving metastasis in gastric carcinoma

BACKGROUND

Cancer stem cells (CSCs) are at the origin of tumour initiation and progression in gastric adenocarcinoma (GC). However, markers of metastasis-initiating cells remain unidentified in GC. In this study, we characterized CD44 variants expressed in GC and evaluated the tumorigenic and metastatic properties of CD44v3+ cells and their clinical significance in GC patients.

METHODS

Using GC cell lines and patient-derived xenografts, we evaluated CD44+ and CD44v3+ GC cells molecular signature and their tumorigenic, chemoresistance, invasive and metastatic properties, and expression in patients-derived tissues.

RESULTS

CD44v3+ cells, which represented a subpopulation of CD44+ cells, were detected in advanced preneoplastic lesions and presented CSCs chemoresistance and tumorigenic properties in vitro and in vivo. Molecular and functional analyses revealed two subpopulations of gastric CSCs: CD44v3+ CSCs with an epithelial-mesenchymal transition (EMT)-like signature, and CD44+/v3- CSCs with an epithelial-like signature; both were tumorigenic but CD44v3+ cells showed higher invasive and metastatic properties in vivo. CD44v3+ cells detected in the primary tumours of GC patients were associated with a worse prognosis.

CONCLUSION

CD44v3 is a marker of a subpopulation of CSCs with metastatic properties in GC. The identification of metastasis-initiating cells in GC represents a major advance for further development of anti-metastatic therapeutic strategies.

Twist1 as a target for prevention of cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (cSCC) represents an important clinical problem requiring novel approaches for both prevention and treatment. The transcription factor, Twist-related protein 1 (Twist1), has been identified as having a key mechanistic role in the development and progression of cSCC. Studies in relevant mouse models of cSCC have shown that Twist1 regulates epithelial-mesenchymal transition (EMT) and stemness driving progression and metastasis of cSCC. In addition, further research has shown that Twist1 regulates the balance between keratinocyte proliferation and differentiation and therefore impacts earlier stages of cSCC development. Through use of keratinocyte specific Twist1 knockout models, a role for this gene in keratinocyte stem cell homeostasis has been revealed. As a transcription factor, Twist1 regulates a large number of genes both in a positive, as well as a negative manner across several interdependent pathways. Studies in keratinocyte specific knockout models have shown that Twist1 upregulates the expression of genes involved in proliferation, stemness, and EMT while downregulating the expression of genes associated with differentiation. Furthermore, a number of compounds, including naturally occurring compounds, have been identified that target Twist1 and can block its effects in cancer cells and in keratinocytes in vivo. Collectively, the current understanding of Twist1 function in cSCC development and progression suggests that it represents a potential target for prevention and treatment of cSCC.

Lipid Raft Facilitated Receptor Organization and Signaling: A Functional Rheostat in Embryonic Development, Stem Cell Biology and Cancer

Molecular views of plasma membrane organization and dynamics are gradually changing over the past fifty years. Dynamics of plasma membrane instigate several signaling nexuses in eukaryotic cells. The striking feature of plasma membrane dynamics is that, it is internally transfigured into various subdomains of clustered macromolecules. Lipid rafts are nanoscale subdomains, enriched with cholesterol and sphingolipids, reside as floating entity mostly on the exoplasmic leaflet of the lipid bilayer. In terms of functionality, lipid rafts are unique among other membrane subdomains. Herein, advances on the roles of lipid rafts in cellular physiology and homeostasis are discussed, precisely, on how rafts dynamically harbor signaling proteins, including GPCRs, catalytic receptors, and ionotropic receptors within it and orchestrate multiple signaling pathways. In the developmental proceedings signaling are designed for patterning of overall organism and they differ from the somatic cell physiology and signaling of fully developed organisms. Some of the developmental signals are characteristic in maintenance of stemness and activated during several types of tumor development and cancer progression. The harmony between extracellular signaling and lineage specific transcriptional programs are extremely important for embryonic development. The roles of plasma membrane lipid rafts mediated signaling in lineage specificity, early embryonic development, stem cell maintenance are emerging. In view of this, we have highlighted and analyzed the roles of lipid rafts in receptor organization, cell signaling, and gene expression during embryonic development; from pre-implantation through the post-implantation phase, in stem cell and cancer biology.

CD73-generated extracellular adenosine promotes resolution of neutrophil-mediated tissue injury and restrains metaplasia in pancreatitis

Pancreatitis is currently the leading cause of gastrointestinal hospitalizations in the US. This condition occurs in response to abdominal injury, gallstones, chronic alcohol consumption or, less frequently, the cause remains idiopathic. CD73 is a cell surface ecto-5'-nucleotidase that generates extracellular adenosine, which can contribute to resolution of inflammation by binding adenosine receptors on infiltrating immune cells. We hypothesized genetic deletion of CD73 would result in more severe pancreatitis due to decreased generation of extracellular adenosine. CD73 knockout (CD73-/- ) and C57BL/6 (wild type, WT) mice were used to evaluate the progression and response of caerulein-induced acute and chronic pancreatitis. In response to caerulein-mediated chronic or acute pancreatitis, WT mice display resolution of pancreatitis at earlier timepoints than CD73-/- mice. Using immunohistochemistry and analysis of single-cell RNA-seq (scRNA-seq) data, we determined CD73 localization in chronic pancreatitis is primarily observed in mucin/ductal cell populations and immune cells. In murine pancreata challenged with caerulein to induce acute pancreatitis, we compared CD73-/- to WT mice and observed a significant infiltration of Ly6G+, MPO+, and Granzyme B+ cells in CD73-/- compared to WT pancreata and we quantified a significant increase in acinar-to-ductal metaplasia demonstrating sustained metaplasia and inflammation in CD73-/- mice. Using neutrophil depletion in CD73-/- mice, we show neutrophil depletion significantly reduces metaplasia defined by CK19+ cells per field and significantly reduces acute pancreatitis. These data identify CD73 enhancers as a potential therapeutic strategy for patients with acute and chronic pancreatitis as adenosine generation and activation of adenosine receptors is critical to resolve persistent inflammation in the pancreas.

PPAR-δ as a prognostic biomarker and its association with immune infiltrates in breast cancer PPAR-δ as a prognostic biomarker and its association with immune infiltrates in breast cancer

While peroxisome proliferator-activated receptor δ (PPAR-δ) and its associated signaling pathways have been shown to play an important regulatory role in various malignant tumors, in breast cancer, its potential influence on immune infiltration and its ability to serve as a prognostic marker remains unclear. BRCA patient samples with matched paracancerous samples were obtained from The Cancer Genome Atlas (TCGA). PPAR-δ expression, its potential effect on immune cell infiltration and its association to clinicopathological features were examined. Gene Ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG), Gene Set Enrichment Analysis (GSEA) and Single-Sample Gene Set Enrichment Analysis (ssGSEA) were utilized for functional and pathway enrichment and to quantify the extent of immune cell infiltration. Kaplan-Meier analysis and Cox regression analysis (nomogram) were performed to assess the association between PPAR- δ and predicted survival. To confirm these findings, an allograft tumor mouse model was generated and treated with a PPAR-δ inhibitor to examine the role of PPAR-δ expression in vivo; while immunohistochemistry (IHC) was performed to examine PPAR-δ expression in paired BRCA patient samples in vitro. Overall, the findings presented herein suggest that PPAR-δ plays a crucial role in breast cancer progression and prognosis and may serve as a survival predictive biomarker.

Breaking the niche: multidimensional nanotherapeutics for tumor microenvironment modulation

Most of the current antitumor therapeutics were developed targeting the cancer cells only. Unfortunately, in the majority of tumors, this single-dimensional therapy is found to be ineffective. Advanced research has shown that cancer is a multicellular disorder. The tumor microenvironment (TME), which is made by a complex network of the bulk tumor cells and other supporting cells, plays a crucial role in tumor progression. Understanding the importance of the TME in tumor growth, different treatment modalities have been developed targeting these supporting cells. Recent clinical results suggest that simultaneously targeting multiple components of the tumor ecosystem with drug combinations can be highly effective. This type of "multidimensional" therapy has a high potential for cancer treatment. However, tumor-specific delivery of such multi-drug combinations remains a challenge. Nanomedicine could be utilized for the tumor-targeted delivery of such multidimensional therapeutics. In this review, we first give a brief overview of the major components of TME. We then highlight the latest developments in nanoparticle-based combination therapies, where one drug targets cancer cells and other drug targets tumor-supporting components in the TME for a synergistic effect. We include the latest preclinical and clinical studies and discuss innovative nanoparticle-mediated targeting strategies.

Comprehensive Analysis Identifies the PPAR-Targeted Genes Associated with Ovarian Cancer Prognosis and Tumor Microenvironment

Background

There is a significant role for peroxisome proliferator-activated receptors (PPARs) in the development of cancer. Nevertheless, the role of PPARs-related genes in ovarian cancer (OC) remains unclear.

Methods

The open-accessed data used for analysis were downloaded from The Cancer Genome Atlas database, which was analyzed using the R software.

Results

In our study, we comprehensively investigated the PPAR target genes in OC, including their biological role. Meanwhile, a prognosis signature consisting of eight PPAR target genes was established, including apolipoprotein A-V, UDP glucuronosyltransferase 2 family, polypeptide B4, TSC22 domain family, member 1, growth hormone inducible transmembrane protein, renin, dedicator of cytokinesis 4, enoyl CoA hydratase 1, peroxisomal (ECH1), and angiopoietin-like 4, which showed a good prediction efficiency. A nomogram was constructed by combining the clinical feature and risk score. Immune infiltration and biological enrichment analysis were applied to investigate the difference between high- and low-risk patients. Immunotherapy analysis indicated that low-risk patients might respond better to immunotherapy. Drug sensitivity analysis indicated that high-risk patients might respond better to bleomycin, nilotinib, pazopanib, pyrimethamine, and vinorelbine, yet worse to cisplatin and gefitinib. Furthermore, the gene ECH1 was selected for further analysis.

Conclusions

Our study identified a prognosis signature that could effectively indicates patients survival. Meanwhile, our study can provide the direction for future studies focused on the PPARs in OC.

Increasing Stress to Induce Apoptosis in Pancreatic Cancer via the Unfolded Protein Response (UPR)

High rates of cell proliferation and protein synthesis in pancreatic cancer are among many factors leading to endoplasmic reticulum (ER) stress. To restore cellular homeostasis, the unfolded protein response (UPR) activates as an adaptive mechanism through either the IRE1α, PERK, or ATF6 pathways to reduce the translational load and process unfolded proteins, thus enabling tumor cells to proliferate. Under severe and prolonged ER stress, however, the UPR may promote adaptation, senescence, or apoptosis under these same pathways if homeostasis is not restored. In this review, we present evidence that high levels of ER stress and UPR activation are present in pancreatic cancer. We detail the mechanisms by which compounds activate one or many of the three arms of the UPR and effectuate downstream apoptosis and examine available data on the pre-clinical and clinical-phase ER stress inducers with the potential for anti-tumor efficacy in pancreatic cancer. Finally, we hypothesize a potential new approach to targeting pancreatic cancer by increasing levels of ER stress and UPR activation to incite apoptotic cell death.

Characterization of Hyaluronic Acid-Coated PLGA Nanoparticles by Surface-Enhanced Raman Spectroscopy

Nanoparticles (NPs) coated with hyaluronic acid (HA) seem to be increasingly promising for targeted therapy due to HA chemical versatility, which allows them to bind drugs of different natures, and their affinity with the transmembrane receptor CD-44, overexpressed in tumor cells. However, an essential aspect for clinical use of NPs is formulation stability over time. For these reasons, analytical techniques capable of characterizing their physico-chemical properties are needed. In this work, poly(lactide-co-glycolide) (PLGA) NPs with an average diameter of 100-150 nm, coated with a few 10 s of nm of HA, were synthesized. For stability characterization, two complementary investigative techniques were used: Dynamic Light Scattering (DLS) and Surface-Enhanced Raman Scattering (SERS) spectroscopy. The first technique provided information on size, polidispersity index, and zeta-potential, and the second provided a deeper insight on the NP surface chemicals, allowing distinguishing of HA-coated NPs from uncoated ones. Furthermore, in order to estimate formulation stability over time, NPs were measured and monitored for two weeks. SERS results showed a progressive decrease in the signal associated with HA, which, however, is not detectable by the DLS measurements.

Loss of tumor suppressor WWOX accelerates pancreatic cancer development through promotion of TGFβ/BMP2 signaling

Pancreatic cancer is one of the most lethal cancers, owing to its late diagnosis and resistance to chemotherapy. The tumor suppressor WW domain-containing oxidoreductase (WWOX), one of the most active fragile sites in the human genome (FRA16D), is commonly altered in pancreatic cancer. However, the direct contribution of WWOX loss to pancreatic cancer development and progression remains largely unknown. Here, we report that combined conditional deletion of Wwox and activation of KRasG12D in Ptf1a-CreER-expressing mice results in accelerated formation of precursor lesions and pancreatic carcinoma. At the molecular level, we found that WWOX physically interacts with SMAD3 and BMP2, which are known activators of the TGF-β signaling pathway. In the absence of WWOX, TGFβ/BMPs signaling was enhanced, leading to increased macrophage infiltration and enhanced cancer stemness. Finally, overexpression of WWOX in patient-derived xenografts led to diminished aggressiveness both in vitro and in vivo. Overall, our findings reveal an essential role of WWOX in pancreatic cancer development and progression and underscore its role as a bona fide tumor suppressor.

Identification of an Immune-Related Gene Signature Associated with Prognosis and Tumor Microenvironment in Esophageal Cancer

Background

Esophageal cancer (EC) is a common malignant tumor of the digestive system with high mortality and morbidity. Current evidence suggests that immune cells and molecules regulate the initiation and progression of EC. Accordingly, it is necessary to identify immune-related genes (IRGs) affecting the biological behaviors and microenvironmental characteristics of EC.

Methods

Bioinformatics methods, including differential expression analysis, Cox regression, and immune infiltration prediction, were conducted using R software to analyze the Gene Expression Omnibus (GEO) dataset. The Cancer Genome Atlas (TCGA) cohort was used to validate the prognostic signature. Patients were stratified into high- and low-risk groups for further analyses, including functional enrichment, immune infiltration, checkpoint relevance, clinicopathological characteristics, and therapeutic sensitivity analyses.

Results

A prognostic signature was established based on 21 IRGs (S100A7, S100A7A, LCN1, CR2, STAT4, GAST, ANGPTL5, TRAV39, F2RL2, PGLYRP3, KLRD1, TRIM36, PDGFA, SLPI, PCSK2, APLN, TICAM1, ITPR3, MAPK9, GATA4, and PLAU). Compared with high-risk patients, better overall survival rates and clinicopathological characteristics were found in low-risk patients. The areas under the curve of the two cohorts were 0.885 and 0.718, respectively. Higher proportions of resting CD4⁺ memory T lymphocytes, M2 macrophages, and resting dendritic cells and lower proportions of follicular helper T lymphocytes, plasma cells, and neutrophils were found in the high-risk tumors. Moreover, the high-risk group showed higher expression of CD44 and TNFSF4, lower expression of PDCD1 and CD40, and higher TIDE scores, suggesting they may respond poorly to immunotherapy. High-risk patients responded better to chemotherapeutic agents such as docetaxel, doxorubicin, and gemcitabine. Furthermore, IRGs associated with tumor progression, including PDGFA, ITPR3, SLPI, TICAM1, and GATA4, were identified.

Conclusion

Our immune-related signature yielded reliable value in evaluating the prognosis, microenvironmental characteristics, and therapeutic sensitivity of EC and may help with the precise treatment of this patient population.

SOX2-high cancer cells exhibit an aggressive phenotype, with increases in stemness, proliferation and invasion, as well as higher metabolic activity and ATP production

Cancer stem cells (CSCs) are responsible for cancer recurrence, treatment failure and metastatic dissemination. As such, the elimination of CSCs represents one of the most important approaches for the future of cancer treatment. Among other properties, CSCs show the activation of particular cell signalling pathways and the over-expression of certain transcription factors, such as SOX2. Herein, we describe a new model system to isolate stem-like cancer cells, based on the functional transcriptional activity of SOX2. Briefly, we employed a SOX2-enhancer-GFP-reporter system to isolate cancer cells with high SOX2 transcriptional activity by FACS sorting. The over-expression of SOX2 in this sub-population was validated by Western blot analysis and flow cytometry. SOX2-high cancer cells showed CSCs features, such as greater mammosphere forming ability, validating that this sub-population was enriched in CSCs. To further explore the model, we analysed other stemness characteristics in MCF7 and MDA-MB-231 breast cancer cell lines, corroborating that SOX2-high cells were more metabolically active, proliferative, migratory, invasive, and drug-resistant. SOX2-high MDA-MB-231 cells also showed a loss of E-cadherin expression, and increased Vimentin expression, consistent with an epithelial-mesenchymal transition (EMT). Therefore, endogenous SOX2 transcriptional activity and protein levels are mechanistically linked to aggressive phenotypic behaviours and energy production in CSCs.

[Advances in the Study of Tissue-resident Memory T Cells in Lung Cancer]

Immune checkpoint inhibitors (ICIs) have been widely used in the treatment of lung cancer, but the benefit population is limited and there is a lack of effective predictive markers of efficacy. Tissue-resident memory T cells (TRM) reside in tissues and exert anti-tumor effects by expressing the integrins CD103, CD49a or C-type lectin CD69 and immune checkpoint receptors. TRM expressing programmed cell death 1 (PD-1) is enriched with transcriptional products associated with cytotoxicity and enhances T cell (antigen) receptor (TCR)-mediated cytotoxicity. TRM is a promising biomarker for predicting the efficacy and prognosis of immunotherapy in lung cancer patients. This review will describe the progress of TRM research in lung cancer.
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USPs in Pancreatic Ductal Adenocarcinoma: A Comprehensive Bioinformatic Analysis of Expression, Prognostic Significance, and Immune Infiltration

Pancreatic ductal adenocarcinoma (PDAC), as an intractable malignancy, still causes an extremely high mortality worldwide. The ubiquitin-specific protease (USP) family constitutes the major part of deubiquitinating enzymes (DUBs) which has been reported to be involved in initiation and progression of various malignancies via the function of deubiquitination. However, the biological function and clinical values of USPs in PDAC have not been comprehensively elucidated. In this study, Gene Expression Profiling Interactive Analysis (GEPIA), Gene Expression Omnibus (GEO) datasets, UALCAN database, and the Human Protein Atlas (HPA) online tool were used to analyze the expression level and the relationship between USP expression and clinicopathological features in PDAC. Survival module of HPA and Kaplan-Meier plotter (KMP) databases was recruited to explore the prognostic value of USPs. Tumor Immune Estimation Resource (TIMER) online tool and KMP databases were utilized to elucidate tumor immune infiltration and immune-related survival of USPs. CBioPortal online tool was used to identify the gene mutation level of USPs in PDAC. Both cBioPortal and LinkedOmics were used to confirm the potential biological functions of USPs in PDAC. Our study showed that USP10, USP14, USP18, USP32, USP33, and USP39 (termed as six-USPs) expressions were significantly elevated in tumor tissues. The high expression of the four USPs (USP10, USP14, USP18, and USP39) indicated a poor prognosis. A significant relationship was indicated between the expression of six-USPs and clinicopathological features. Also, the expression of six-USPs was related to promoter methylation level. Moreover, more than 40% genetic alterations and mutations were discovered in six-USPs. Furthermore, the six-USP expression was correlated with immune infiltration and immune-related prognosis. The functional analysis found that the six-USPs were involved in various biological processes and signaling pathways, such as nucleocytoplasmic transport, choline metabolism in cancer, cell cycle, ErbB signaling pathway, RIG-I-like receptor signaling pathway, TGF-β signaling pathway, and TNF signaling pathway. In conclusion, the results showed that six-USPs are potential prognostic biomarkers and can be recruited as possible therapeutic targets of PDAC.

Current Update on Biomarkers for Detection of Cancer: Comprehensive Analysis

Early and effective diagnosis of cancer is decisive for its proper management. In this context biomarker-based cancer diagnosis is budding as one of the promising ways for early detection, disease progression monitoring, and effective cancer therapy. Integration of Biosensing devices with different metallic/nonmetallic nanoparticles offers amplification and multiplexing capabilities for simultaneous detection of cancer biomarkers (CB's). This study provides a comprehensive analysis of the most recent designs and fabrication methodologies designed for developing electrochemical biosensors (EB) for early detection of cancers. The role of biomarkers in cancer therapeutics is also discussed.

ITGA2 induces STING expression in pancreatic cancer by inducing DNMT1 degradation

PURPOSE

Integrin alpha 2 (ITGA2, also known as CD49b or VLA-2) is the alpha subunit of a transmembrane receptor for collagens and related proteins. Previously, we found that ITGA2 may regulate immune cell infiltration in pancreatic cancer by inducing PD-L1 expression. As yet, however, whether ITGA2 regulates immune cell infiltration in pancreatic cancer by other mechanisms remains unclear.

METHODS

RNA sequencing was performed to identify differentially expressed genes in ITGA2-silenced pancreatic cancer cells. Protein-protein interactions were detected via co-immunoprecipitation. The infiltration level of immune cells was assessed using an immunofluorescence staining assay.

RESULTS

We found that ITGA2 can activate the cytosolic DNA-sensing pathway and promote STING expression in pancreatic cancer cells. In addition, we found that ITGA2 induces DNMT1 degradation by disrupting the interaction between DNMT1 and Kindlin2 in pancreatic cancer cells. As a DNA methyltransferase, we found that DNMT1 overexpression induced by ITGA2 silencing significantly up-regulated the methylation level of the STING gene promoter. Finally, ITGA2 silencing combined with DNMT1 inhibitor treatment induced immune cell infiltration in pancreatic cancer.

CONCLUSION

Our data indicate that ITGA2 induces STING expression by interacting with DNMT1 and inducing the degradation of DNMT1. ITGA2 silencing combined with DNMT1 inhibitor treatment may be a novel therapeutic strategy for pancreatic cancer.

Inside the stemness engine: Mechanistic links between deregulated transcription factors and stemness in cancer

Cell identity is largely determined by its transcriptional profile. In tumour, deregulation of transcription factor expression and/or activity enables cancer cell to acquire a stem-like state characterised by capacity to self-renew, differentiate and form tumours in vivo. These stem-like cancer cells are highly metastatic and therapy resistant, thus warranting a more complete understanding of the molecular mechanisms downstream of the transcription factors that mediate the establishment of stemness state. Here, we review recent research findings that provide a mechanistic link between the commonly deregulated transcription factors and stemness in cancer. In particular, we describe the role of master transcription factors (SOX, OCT4, NANOG, KLF, BRACHYURY, SALL, HOX, FOX and RUNX), signalling-regulated transcription factors (SMAD, β-catenin, YAP, TAZ, AP-1, NOTCH, STAT, GLI, ETS and NF-κB) and unclassified transcription factors (c-MYC, HIF, EMT transcription factors and P53) across diverse tumour types, thereby yielding a comprehensive overview identifying shared downstream targets, highlighting unique mechanisms and discussing complexities.

Transcription factors TEAD2 and E2A globally repress acetyl-CoA synthesis to promote tumorigenesis

Acetyl-coenzyme A (acetyl-CoA) plays an important role in metabolism, gene expression, signaling, and other cellular processes via transfer of its acetyl group to proteins and metabolites. However, the synthesis and usage of acetyl-CoA in disease states such as cancer are poorly characterized. Here, we investigated global acetyl-CoA synthesis and protein acetylation in a mouse model and patient samples of hepatocellular carcinoma (HCC). Unexpectedly, we found that acetyl-CoA levels are decreased in HCC due to transcriptional downregulation of all six acetyl-CoA biosynthesis pathways. This led to hypo-acetylation specifically of non-histone proteins, including many enzymes in metabolic pathways. Importantly, repression of acetyl-CoA synthesis promoted oncogenic dedifferentiation and proliferation. Mechanistically, acetyl-CoA synthesis was repressed by the transcription factors TEAD2 and E2A, previously unknown to control acetyl-CoA synthesis. Knockdown of TEAD2 and E2A restored acetyl-CoA levels and inhibited tumor growth. Our findings causally link transcriptional reprogramming of acetyl-CoA metabolism, dedifferentiation, and cancer.

The long noncoding RNA TINCR promotes self-renewal of human liver cancer stem cells through autophagy activation

Hepatocellular carcinoma (HCC) is an extraordinarily heterogeneous tumor, which holds high recurrence and metastasis rates. Liver cancer stem cells (LCSCs) have been considered to be important influencing factors of these pathological properties, but the underlying mechanisms are poorly understood in HCC. Considerable evidences have shown that autophagy has an important role in cancer stemness. However, it is still unknown whether a long noncoding RNA (lncRNA) TINCR is involved in autophagy and self-renewal maintenance of HCC. In this study, TINCR was found to be highly expressed in HCC tissues and LCSCs. In vitro and in vivo assays for the first time showed that TINCR was required for LCSC self-renewal and tumorigenesis. Moreover, gene ontology analysis revealed the involvement of autophagy in the maintenance of TINCR-regulated stemness. Mechanically, TINCR was associated with polypyrimidine tract binding protein 1 (PTBP1) protein, which further promoted the transcription activity of autophagy related gene ATG5. In conclusion, we demonstrated that TINCR regulated LCSC self-renewal by autophagy activation through PTBP1/ATG5 regulatory pathway, offering a potential new target for HCC therapy.