Inhibition of pyruvate carboxylase by 1α,25-dihydroxyvitamin D promotes oxidative stress in early breast cancer progression

1α,25-Dihydroxyvitamin D Downregulates Adipocyte Impact on Breast Cancer Cell Migration and Adipokine Release

BACKGROUND/OBJECTIVES

Excess adiposity is associated with a higher risk of breast cancer metastasis and mortality. Evidence suggests that dietary vitamin D inhibits breast cancer metastasis. However, the mechanistic link between vitamin D's regulation of adipocyte metabolism and metastasis has not been previously investigated. Therefore, the purpose of these experiments was to examine the effect of the active form of vitamin D, 1α,25-dihydroxyvitamin D (1,25(OH)2D), on adipocyte release of bioactive compounds and whether the impact on adipocytes leads to inhibition of breast cancer cell migration, an important step of metastasis.

METHODS

Differentiated 3T3-L1 adipocytes were treated with 1,25(OH)2D for two days, followed by either harvesting the adipocytes or collecting adipocyte-conditioned media without 1,25(OH)2D. A transwell migration assay was conducted with vehicle- or 1,25(OH)2D-conditioned media. In order to explore the mechanism underlying effects on breast cancer metastatic capability, the mRNA expression of leptin, adiponectin, insulin-like growth factor (IGF-1), interleukin-6 (IL-6), and monocyte chemoattractant protein-1 (MCP-1) was measured in adipocytes following either vehicle or 1,25(OH)2D treatment.

RESULTS

Conditioned media from 1,25(OH)2D-treated adipocytes inhibited the migration of metastatic MDA-MB-231 breast cancer cells compared to conditioned media from vehicle-treated adipocytes. Treatment of adipocytes with 1,25(OH)2D decreased mRNA expression of leptin, adiponectin, IGF-1, IL-6, and MCP-1. Consistent with mRNA expression, concentrations of leptin, adiponectin, IGF-1, and IL-6 in adipocyte-conditioned media were decreased with 1,25(OH)2D treatment, although MCP-1 remained unchanged.

CONCLUSIONS

In summary, these results suggest that 1,25(OH)2D alters adipocyte secretions to prevent breast cancer metastasis.

Pyruvate Carboxylase Attenuates Myocardial Ischemia-Reperfusion Injury in Heart Transplantation via Wnt/β-Catenin-Mediated Glutamine Metabolism

The ischemia-reperfusion process of a donor heart during heart transplantation leads to severe mitochondrial dysfunction, which may be the main cause of donor heart dysfunction after heart transplantation. Pyruvate carboxylase (PC), an enzyme found in mitochondria, is said to play a role in the control of oxidative stress and the function of mitochondria. This research examined the function of PC and discovered the signaling pathways controlled by PC in myocardial IRI. We induced IRI using a murine heterotopic heart transplantation model in vivo and a hypoxia-reoxygenation cell model in vitro and evaluated inflammatory responses, oxidative stress levels, mitochondrial function, and cardiomyocyte apoptosis. In both in vivo and in vitro settings, we observed a significant decrease in PC expression during myocardial IRI. PC knockdown aggravated IRI by increasing MDA content, LDH activity, TUNEL-positive cells, serum cTnI level, Bax protein expression, and the level of inflammatory cytokines and decreasing SOD activity, GPX activity, and Bcl-2 protein expression. PC overexpression yielded the opposite findings. Additional research indicated that reducing PC levels could block the Wnt/β-catenin pathway and glutamine metabolism by hindering the movement of β-catenin to the nucleus and reducing the activity of complex I and complex II, as well as ATP levels, while elevating the ratios of NADP+/NADPH and GSSG/GSH. Overall, the findings indicated that PC therapy can shield the heart from IRI during heart transplantation by regulating glutamine metabolism through the Wnt/β-catenin pathway.

Exploring variations in glycolytic and gluconeogenic enzymes and isoforms across breast cancer cell lines and tissues

It is well established that tumour cells undergo metabolic changes to acquire biological advantage over normal cells with activation of the glycolytic pathway, a process termed "Warburg effect". Enzyme isoforms are alternative enzymatic forms with the same function but with different biochemical or epigenetic features. Moreover, isoforms may have varying impacts on different metabolic pathways. We challenge ourselves to analyse the glycolytic and gluconeogenic enzymes and isoforms in breast cancer, a complex and heterogeneous pathology, associated with high incidence and mortality rates especially among women. We analysed epithelial and tumour cell lines by RT-PCR and compared values to a publicly available database for the expression profile of normal and tumour tissues (Gepia) of enzymes and enzymatic isoforms from glycolytic and gluconeogenic pathways. Additionally, GeneMANIA was used to evaluate interactions, pathways, and attributes of each glycolytic/gluconeogenic steps. The findings reveal that the enzymes and enzymatic isoforms expressed in cell culture were somewhat different from those in breast tissue. We propose that the tumor microenvironment plays a crucial role in the expression of glycolytic and gluconeogenic enzymes and isoforms in tumour cells. Nonetheless, they not only participate in glycolytic and gluconeogenic enzymatic activities but may also influence other pathways, such as the Pentose-Phosphate-Pathway, TCA cycle, as well as other carbohydrate, lipid, and amino acid metabolism.

Hypoxia-mediated repression of pyruvate carboxylase drives immunosuppression

BACKGROUND

Metabolic plasticity mediates breast cancer survival, growth, and immune evasion during metastasis. However, how tumor cell metabolism is influenced by and feeds back to regulate breast cancer progression are not fully understood. We identify hypoxia-mediated suppression of pyruvate carboxylase (PC), and subsequent induction of lactate production, as a metabolic regulator of immunosuppression.

METHODS

We used qPCR, immunoblot, and reporter assays to characterize repression of PC in hypoxic primary tumors. Steady state metabolomics were used to identify changes in metabolite pools upon PC depletion. In vivo tumor growth and metastasis assays were used to evaluate the impact of PC manipulation and pharmacologic inhibition of lactate transporters. Immunohistochemistry, flow cytometry, and global gene expression analyzes of tumor tissue were employed to characterize the impact of PC depletion on tumor immunity.

RESULTS

PC is essential for metastatic colonization of the lungs. In contrast, depletion of PC in tumor cells promotes primary tumor growth. This effect was only observed in immune competent animals, supporting the hypothesis that repression of PC can suppress anti-tumor immunity. Exploring key differences between the pulmonary and mammary environments, we demonstrate that hypoxia potently downregulated PC. In the absence of PC, tumor cells produce more lactate and undergo less oxidative phosphorylation. Inhibition of lactate metabolism was sufficient to restore T cell populations to PC-depleted mammary tumors.

CONCLUSIONS

We present a dimorphic role for PC in primary mammary tumors vs. pulmonary metastases. These findings highlight a key contextual role for PC-directed lactate production as a metabolic nexus connecting hypoxia and antitumor immunity.

The adipose-derived stem cell peptide ADSCP2 alleviates hypertrophic scar fibrosis via binding with pyruvate carboxylase and remodeling the metabolic landscape

AIM

The purpose of this study was to investigate the function and mechanism of a novel peptide derived from adipose-derived stem cell-conditioned medium (ADSC-CM).

METHODS

Mass spectrometry was applied to identify expressed peptides in ADSC-CM obtained at different time points. The cell counting kit-8 assay and quantitative reverse transcription polymerase chain reactions were performed to screen the functional peptides contained within ADSC-CM. RNA-seq, western blot, a back skin excisional model of BALB/c mice, the peptide pull-down assay, rescue experiments, untargeted metabolomics, and mixOmics analysis were performed to thoroughly understand the functional mechanism of selected peptide.

RESULTS

A total of 93, 827, 1108, and 631 peptides were identified in ADSC-CM at 0, 24, 48, and 72 h of conditioning, respectively. A peptide named ADSCP2 (DENREKVNDQAKL) derived from ADSC-CM inhibited collagen and ACTA2 mRNAs in hypertrophic scar fibroblasts. Moreover, ADSCP2 facilitated wound healing and attenuated collagen deposition in a mouse model. ADSCP2 bound with the pyruvate carboxylase (PC) protein and inhibited PC protein expression. Overexpressing PC rescued the reduction in collagen and ACTA2 mRNAs caused by ADSCP2. Untargeted metabolomics identified 258 and 447 differential metabolites in the negative and positive mode, respectively, in the ADSCP2-treated group. The mixOmics analysis, which integrated RNA-seq and untargeted metabolomics data, provided a more holistic view of the functions of ADSCP2.

CONCLUSION

Overall, a novel peptide derived from ADSC-CM, named ADSCP2, attenuated hypertrophic scar fibrosis in vitro and in vivo, and the novel peptide ADSCP2 might be a promising drug candidate for clinical scar therapy.

Immunodetection of Pyruvate Carboxylase Expression in Human Astrocytomas, Glioblastomas, Oligodendrogliomas, and Meningiomas

Pyruvate carboxylase (PC) is an enzyme catalyzing the carboxylation of pyruvate to oxaloacetate. The enzymatic generation of oxaloacetate, an intermediate of the Krebs cycle, could provide the cancer cells with the additional anaplerotic capacity and promote their anabolic metabolism. Recent studies revealed that several types of cancer cells express PC. The gained anaplerotic capability of cells mediated by PC correlates with their expedited growth, higher aggressiveness, and increased metastatic potential. By immunohistochemical staining and immunoblotting analysis, we investigated PC expression among samples of different types of human brain tumors. Our results show that PC is expressed by the cells in glioblastoma, astrocytoma, oligodendroglioma, and meningioma tumors. The presence of PC in these tumors suppose that PC could support the anabolic metabolism of their cellular constituents by its anaplerotic capability.

Pyruvate carboxylase promotes malignant transformation of papillary thyroid carcinoma and reduces iodine uptake

Previous studies have shown that pyruvate carboxylase (PC) plays a key role in the occurrence and progression of thyroid cancer (TC); however, the relationship between PC and iodine-refractory TC is unclear. Therefore, the present study aimed to investigate the molecular mechanism of PC in the malignant progression and loss of iodine uptake in papillary TC (PTC) and to explore the potential therapeutic effect of PC inhibitors in iodine-refractory PTC. PC increased cell proliferation, invasion, and metastasis, inhibited expression of the iodine metabolism-related genes TSHR, NIS, TPO, and TG, and decreased the iodine-uptake capacity by activating the mitogen-activated protein kinase/extracellular signal-regulated kinase pathway in PTC cell lines. Furthermore, the PC inhibitor ZY-444 effectively inhibited the activation of PC, reduced the malignant invasiveness, and restored the expression of iodine metabolism-related genes and the iodine-uptake capacity in PTC cells. These findings suggest that PC activation is involved in the progression of iodine-refractory TC and that PC inhibitors may represent a potentially novel targeted therapy for iodine-refractory TC.

Hypoxia-Mediated ATF4 Induction Promotes Survival in Detached Conditions in Metastatic Murine Mammary Cancer Cells

Regions of hypoxia are common in solid tumors and drive changes in gene expression that increase risk of cancer metastasis. Tumor cells must respond to the stress of hypoxia by activating genes to modify cell metabolism and antioxidant response to improve survival. The goal of the current study was to determine the effect of hypoxia on cell metabolism and markers of oxidative stress in metastatic (metM-Wntlung) compared with nonmetastatic (M-Wnt) murine mammary cancer cell lines. We show that hypoxia induced a greater suppression of glutamine to glutamate conversion in metastatic cells (13% in metastatic cells compared to 7% in nonmetastatic cells). We also show that hypoxia increased expression of genes involved in antioxidant response in metastatic compared to nonmetastatic cells, including glutamate cysteine ligase catalytic and modifier subunits and malic enzyme 1. Interestingly, hypoxia increased the mRNA level of the transaminase glutamic pyruvic transaminase 2 (Gpt2, 7.7-fold) only in metM-Wntlung cells. The change in Gpt2 expression was accompanied by transcriptional (4.2-fold) and translational (6.5-fold) induction of the integrated stress response effector protein activating transcription factor 4 (ATF4). Genetic depletion ATF4 demonstrated importance of this molecule for survival of hypoxic metastatic cells in detached conditions. These findings indicate that more aggressive, metastatic cancer cells utilize hypoxia for metabolic reprogramming and induction of antioxidant defense, including activation of ATF4, for survival in detached conditions.

The overall process of metastasis: From initiation to a new tumor

Metastasis-a process that involves the migration of cells from the primary site to distant organs-is the leading cause of cancer-associated death. Improved technology and in-depth research on tumors have furthered our understanding of the various mechanisms involved in tumor metastasis. Metastasis is initiated by cancer cells of a specific phenotype, which migrate with the assistance of extracellular components and metastatic traits conferred via epigenetic regulation while modifying their behavior in response to the complex and dynamic human internal environment. In this review, we have summarized the general steps involved in tumor metastasis and their characteristics, incorporating recent studies and topical issues, including epithelial-mesenchymal transition, cancer stem cells, neutrophil extracellular traps, pre-metastatic niche, extracellular vesicles, and dormancy. Several feasible treatment directions have also been summarized. In addition, the correlation between cancer metastasis and lifestyle factors, such as obesity and circadian rhythm, has been illustrated.

Increased Ammonium Toxicity in Response to Exogenous Glutamine in Metastatic Breast Cancer Cells

Several cancers, including breast cancers, show dependence on glutamine metabolism. The purpose of the present study was to determine the mechanistic basis and impact of differential glutamine metabolism in nonmetastatic and metastatic murine mammary cancer cells. Universally labeled 13C5-glutamine metabolic tracing, qRT-PCR, measures of reductive-oxidative balance, and exogenous ammonium chloride treatment were used to assess glutamine reprogramming. Results show that 4 mM media concentration of glutamine, compared with 2 mM, reduced viability only in metastatic cells, and that this decrease in viability was accompanied by increased incorporation of glutamine-derived carbon into the tricarboxylic acid (TCA) cycle. While increased glutamine metabolism in metastatic cells occurred in tandem with a decrease in the reduced/oxidized glutathione ratio, treatment with the antioxidant molecule N-acetylcysteine did not rescue cell viability. However, the viability of metastatic cells was more sensitive to ammonium chloride treatment compared with nonmetastatic cells, suggesting a role of metabolic reprogramming in averting nitrogen cytotoxicity in nonmetastatic cells. Overall, these results demonstrate the ability of nonmetastatic cancer cells to reprogram glutamine metabolism and that this ability may be lost in metastatic cells.

Metabolic Reprogramming Underlying Brain Metastasis of Breast Cancer

The development of brain metastasis is a major cause of death in patients with breast cancer, characterized by rapid progression of the disease and poor prognosis, and lack of effective treatment has existed as an unresolved issue clinically. Extensive research has shown that a variety of metabolic changes associated with cellular metastasis exist in primary breast cancer or brain metastases, therefore to elucidate metabolic characteristics at each step of the metastasis cascade will provide important clues to the efficient treatment. In this review, we discuss the changes in metabolic patterns of breast cancer cells at every step of metastasis for exploring the potential therapeutic target based on metabolic reprogramming, and provide new insights on the design and development of drugs for breast cancer brain metastasis.

Identification of Pyruvate Carboxylase as the Cellular Target of Natural Bibenzyls with Potent Anticancer Activity against Hepatocellular Carcinoma via Metabolic Reprogramming

Cancer cell proliferation in some organs often depends on conversion of pyruvate to oxaloacetate via pyruvate carboxylase (PC) for replenishing the tricarboxylic acid cycle to support biomass production. In this study, PC was identified as the cellular target of erianin using the photoaffinity labeling-click chemistry-based probe strategy. Erianin potently inhibited the enzymatic activity of PC, which mediated the anticancer effect of erianin in human hepatocellular carcinoma (HCC). Erianin modulated cancer-related gene expression and induced changes in metabolic intermediates. Moreover, erianin promotes mitochondrial oxidative stress and inhibits glycolysis, leading to insufficient energy required for cell proliferation. Analysis of 14 natural analogs of erianin showed that some compounds exhibited potent inhibitory effects on PC. These results suggest that PC is a cellular target of erianin and reveal the unrecognized function of PC in HCC tumorigenesis; erianin along with its analogs warrants further development as a novel therapeutic strategy for the treatment of HCC.

Vitamin D and Breast Cancer: Mechanistic Update

The presence of the vitamin D receptor (VDR) in mammary gland and breast cancer has long been recognized, and multiple preclinical studies have demonstrated that its ligand, 1,25-dihydroxyvitamin D (1,25D), modulates normal mammary gland development and inhibits growth of breast tumors in animal models. Vitamin D deficiency is common in breast cancer patients, and some evidence suggests that low vitamin D status enhances the risk for disease development or progression. Although many 1,25D-responsive targets in normal mammary cells and in breast cancers have been identified, validation of specific targets that regulate cell cycle, apoptosis, autophagy, and differentiation, particularly in vivo, has been challenging. Model systems of carcinogenesis have provided evidence that both VDR expression and 1,25D actions change with transformation, but clinical data regarding vitamin D responsiveness of established tumors is limited and inconclusive. Because breast cancer is heterogeneous, the relevant VDR targets and potential sensitivity to vitamin D repletion or supplementation will likely differ between patient populations. Detailed analysis of VDR actions in specific molecular subtypes of the disease will be necessary to clarify the conflicting data. Genomic, proteomic, and metabolomic analyses of in vitro and in vivo model systems are also warranted to comprehensively understand the network of vitamin D-regulated pathways in the context of breast cancer heterogeneity. This review provides an update on recent studies spanning the spectrum of mechanistic (cell/molecular), preclinical (animal models), and translational work on the role of vitamin D in breast cancer. © 2021 The Author. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Glucose metabolism and pyruvate carboxylase enhance glutathione synthesis and restrict oxidative stress in pancreatic islets

Glucose metabolism modulates the islet β cell responses to diabetogenic stress, including inflammation. Here, we probed the metabolic mechanisms that underlie the protective effect of glucose in inflammation by interrogating the metabolite profiles of primary islets from human donors and identified de novo glutathione synthesis as a prominent glucose-driven pro-survival pathway. We find that pyruvate carboxylase is required for glutathione synthesis in islets and promotes their antioxidant capacity to counter inflammation and nitrosative stress. Loss- and gain-of-function studies indicate that pyruvate carboxylase is necessary and sufficient to mediate the metabolic input from glucose into glutathione synthesis and the oxidative stress response. Altered redox metabolism and cellular capacity to replenish glutathione pools are relevant in multiple pathologies beyond obesity and diabetes. Our findings reveal a direct interplay between glucose metabolism and glutathione biosynthesis via pyruvate carboxylase. This metabolic axis may also have implications in other settings where sustaining glutathione is essential.

The effects of consuming a low-fat yogurt fortified with nano encapsulated vitamin D on serum pro-oxidant-antioxidant balance (PAB) in adults with metabolic syndrome; a randomized control trial

BACKGROUND AND AIM

The current study aimed to assess the effect of fortified yogurt with nano-encapsulated vitamin D on serum pro-oxidant anti-oxidant balance (PAB) in adults with or without metabolic syndrome.

METHODS

In a quadruple blind clinical trial study, 139 adults with an age range of 30-50 years were randomly selected to receive either 1500 IU nano-encapsulated vitamin D fortified yogurt or placebo for ten weeks. Before and after the intervention period, blood sample was taken to determine the serum levels of vitamin D, pro-oxidant-antioxidant balance (PAB), and high-sensitivity C-reactive protein (hs-CRP). The laboratory tests were checked at baseline and at the end of the treatment.

RESULTS

Serum vitamin D increased significantly, from 14.47 ± 6.07 ng/mL to 21.39 ± 6.54 ng/mL (P < 0.001) after ten weeks in the intervention group. Serum hs-CRP and PAB were significantly lower following consumption period in intervention group [1.95(0.4-8.15) g/dL vs. 1.35(0.25-3.62) g/dL; P = 0.013] and (135.19 ± 42.4 HK vs. 115.39 ± 44.69) HK; P = 0.018] respectively. There were no significant differences between the intervention and control groups regarding weight and BMI at the end of the intervention period (p > 0.05).

CONCLUSION

Low-fat yogurt fortified with nano-encapsulated vitamin D was found to reduce serum PAB levels in adults with metabolic syndrome.

PRACTICAL APPLICATION

The findings of the present study indicated that a low-fat yogurt fortified with 1500 IU nano-encapsulated vitamin D for ten weeks, leads to a significant reduction in serum hs-CRP and PAB concentrations highlighted the anti-inflammatory/anti-oxidative effect of vitamin D.

Enhancement of gemcitabine efficacy by K73-03 via epigenetically regulation of miR-421/SPINK1 in gemcitabine resistant pancreatic cancer cells

BACKGROUND

Gemcitabine (GCB) is a first-line chemotherapeutic drug for pancreatic cancer (PCa). However, the resistance begins developing within weeks of chemotherapy. SPINK1 overexpression enhances resistance to chemotherapy. In a recent study, our laboratory established that the oleanolic acid (OA) derivative, K73-03, had a strong inhibitory effect on a SPINK1 overexpressed PCa cells.

PURPOSE

In our current study, we studied the enhancement of GCB inhibitory effect by K73-03, a new novel OA derivative, alone or in combination with GCB on the GCB-resistant PCa cells by mitochondrial damage through regulation of the miR-421/SPINK1.

METHODS

We detected the binding between miR-421 and SPINK1-3'-UTR in GCB-resistant PCa cells using Luciferase reporter assays. Cells viability, apoptosis, migration, and mitochondrial damage were investigated.

RESULTS

The results demonstrated that the combination of K73-03 and GCB suppressed the growth of AsPC-1 and MIA PaCa-2 cells synergistically, with or without GCB resistance. Mechanistic findings showed that a combination of K73-03 and GCB silences SPINK1 epigenetically by miR-421 up-regulating, which leads to mitochondrial damage and inducing apoptosis in GCB-resistant PCa cells.

CONCLUSION

We found an interesting finding that the 73-03 in combination with GCB can improve GCB efficacy and decrease PCa resistance, which induced apoptosis and mitochondrial damage through epigenetic inhibition of SPINK1 transcription by miR-421 up-regulation. This was the first study that used OA derivatives on GCB-resistant PCa cells, so this combined strategy warrants further investigation.

Adverse Effects and Safety of Etirinotecan Pegol, a Novel Topoisomerase Inhibitor, in Cancer Treatment: A Systematic Review

Background:

Due to the increasing prevalence of cancer and the inadequacy of current therapies, the development of novel antitumor pharmaceutics with higher efficacies and lower adverse effects is considered a fundamental tenet of contemporary cancer management. Poly-Ethylene-Glycol (PEG) attachment is a novel pharmaceutical technology to improve the efficacy and safety of chemotherapies. Etirinotecan Pegol (EP), also known as NKTR-102, is the PEGylated form of Irinotecan (CPT-11), which causes cancer cell apoptosis by inhibiting the topoisomerase I enzyme.

Objectives:

The present study reviews and evaluates various reports of the EP’s anti-tumor activity in various cancers.

Data Sources:

Studies were identified using the Scopus database, with no exclusions. The search terms included Etirinotecan Pegol and NKTR-102, which yielded 125 articles (66 and 59 articles, respectively). In addition, the clinicaltrials.gov website was used to find ongoing studies, which resulted in the addition of two studies.

Study Eligibility Criteria:

Subsequently, we excluded studies that were published in languages other than English, duplicate articles, and studies with no data.

Results:

This systematic review clarifies that EP possesses numerous advantages over many other medications, such as safety, efficacy, increased half-life, increased health-related quality of life, increased overall survival, increased progression-free survival, and decreasing the adverse events in the treatment of various cancers.

Conclusion:

Therefore, Etirinotecan Pegol may represent a major contribution to the treatment of various cancers in the future.

Caffeic acid and its derivatives as potential modulators of oncogenic molecular pathways: New hope in the fight against cancer

As a phenolic acid compound, caffeic acid (CA) can be isolated from different sources such as tea, wine and coffee. Caffeic acid phenethyl ester (CAPE) is naturally occurring derivative of CA isolated from propolis. This medicinal plant is well-known due to its significant therapeutic impact including its effectiveness as hepatoprotective, neuroprotective and anti-diabetic agent. Among them, anti-tumor activity of CA has attracted much attention, and this potential has been confirmed both in vitro and in vivo. CA can induce apoptosis in cancer cells via enhancing ROS levels and impairing mitochondrial function. Molecular pathways such as PI3K/Akt and AMPK with role in cancer progression, are affected by CA and its derivatives in cancer therapy. CA is advantageous in reducing aggressive behavior of tumors via suppressing metastasis by inhibiting epithelial-to-mesenchymal transition mechanism. Noteworthy, CA and CAPE can promote response of cancer cells to chemotherapy, and sensitize them to chemotherapy-mediated cell death. In order to improve capacity of CA and CAPE in cancer suppression, it has been co-administered with other anti-tumor compounds such as gallic acid and p-coumaric acid. Due to its poor bioavailability, nanocarriers have been developed for enhancing its ability in cancer suppression. These issues have been discussed in the present review with a focus on molecular pathways to pave the way for rapid translation of CA for clinical use.

AXL Overexpression in Tumor-Derived Endothelial Cells Promotes Vessel Metastasis in Patients With Hepatocellular Carcinoma

Portal vein tumor thrombus (PVTT) is one of the most serious forms of hepatocellular carcinoma (HCC) vessel metastasis and has a poor survival rate. However, the molecular mechanism of PVTT has not yet been elucidated. In this study, the molecular mechanism of AXL expressed in tumor-derived endothelial cells (TECs) in vessel metastasis was investigated. High AXL expression was observed in TECs, but not in the tumor cells of HCC patients with PVTT and this was associated with poor overall survival (OS) and disease-free survival (DFS). AXL overexpression was positively associated with CD 31 expression both in vitro and in vivo. AXL promoted the cell proliferation, tube formation, and migration of both TECs and normal endothelial cells (NECs). High expression of AXL in TECs promoted the cell migration, but not the proliferation of HCC cells. Further studies demonstrated that AXL promoted cell migration and tube formation through activation of the PI3K/AKT/SOX2/DKK-1 axis. AXL overexpression in HUVECs promoted tumor growth and liver or vessel metastasis of HCC in xenograft nude mice, which could be counteracted by treatment with R428, an AXL inhibitor. R428 reduced tumor growth and CD 31 expression in HCC in PDX xenograft nude mice. Therefore, AXL over-expression in TECs promotes vessel metastasis of HCC, which indicates that AXL in TECs could be a potential therapeutic target in HCC patients with PVTT.

Pyruvate carboxylase and cancer progression

Pyruvate carboxylase (PC) is a mitochondrial enzyme that catalyzes the ATP-dependent carboxylation of pyruvate to oxaloacetate (OAA), serving to replenish the tricarboxylic acid (TCA) cycle. In nonmalignant tissue, PC plays an essential role in controlling whole-body energetics through regulation of gluconeogenesis in the liver, synthesis of fatty acids in adipocytes, and insulin secretion in pancreatic β cells. In breast cancer, PC activity is linked to pulmonary metastasis, potentially by providing the ability to utilize glucose, fatty acids, and glutamine metabolism as needed under varying conditions as cells metastasize. PC enzymatic activity appears to be of particular importance in cancer cells that are unable to utilize glutamine for anaplerosis. Moreover, PC activity also plays a role in lipid metabolism and protection from oxidative stress in cancer cells. Thus, PC activity may be essential to link energy substrate utilization with cancer progression and to enable the metabolic flexibility necessary for cell resilience to changing and adverse conditions during the metastatic process.

Newly-identified Pathways Relating Vitamin D to Carcinogenesis: A Review

BACKGROUND

The epidemiological relationship between vitamin D levels and cancer has been thoroughly investigated. Published data from large studies appear to corroborate a significant relationship between higher serum vitamin D concentrations and improved survival. Mechanistic reviews on commonly-studied cancers - including breast cancer, colon cancer and melanoma - focus predominantly on data from older studies. In outlining avenues for future research, we believe there is utility in summarizing novel findings introduced to the literature.

MATERIALS AND METHODS

In this narrative review, we used MEDLINE, PUBMED and Cochrane databases to identify mechanistic studies published from January 1, 2015 onwards exploring this topic.

RESULTS

Twenty-five mechanistic studies were included in this review. It was found that vitamin D plays a critical role in both direct (i.e. tumor gene expression, proliferation, invasiveness, sensitivity to chemotherapy etc.) and indirect (i.e. effects on the tumor microenvironment and immunomodulation) tumor suppression mechanisms.

CONCLUSION

These newly-identified pathways warrant further research, with the hopes that we may understand how and when vitamin D supplementation can be integrated into precision medicine therapeutics for cancers of the breast, colon and skin. Cancer care providers should consider recommendations to screen for vitamin D deficiency in this population.

Cisplatin-induced ototoxicity: Updates on molecular mechanisms and otoprotective strategies

Cisplatin is a highly effective antitumor drug generally used in the treatment of solid malignant tumors. However, cisplatin causes severe side effects such as bone marrow depression, nephrotoxicity, and ototoxicity, thus limiting its clinical application. The incidence of ototoxicity induced by cisplatin ranges from 20% to 70%, and it usually manifests as a progressive, bilateral and irreversible hearing loss. Although the etiology of cisplatin-induced ototoxicity remains unclear, an increasing body of evidence suggests that the ototoxicity of cisplatin is mainly related to the production of reactive oxygen species and activation of apoptotic pathway in cochlear tissues. Many drugs have been well proved to protect cisplatin-induced hearing loss in vitro and in vivo. However, the anti-tumor effect of cisplatin is also weakened by systemic administration of those drugs for hearing protection, especially antioxidants. Therefore, establishing a local administration strategy contributes to the otoprotection without affecting the effect of cisplatin. This review introduces the pathology of ototoxicity caused by cisplatin, and focuses on recent developments in the mechanisms and protective strategies of cisplatin-induced ototoxicity.

Exploring the mechanism of Radix Rhei Et Rhizome intervention in intracerebral hemorrhage based on systematic pharmacology and proteomics strategy

OBJECTIVE

To explore the mechanism of Radix Rhei Et Rhizome (Dahuang, DH) intervention in intracerebral hemorrhage (ICH) based on systematic pharmacology and proteomics strategy.

METHODS

The systematic pharmacological strategies were utilized to find the bioactive compounds of Radix Rhei Et Rhizome, predict its potential targets, and collect ICH's disease genes; then, the Cytoscape 3.7.1 software was applied for network construction and network topology analysis. After that, in-depth analysis of the proteomics data of Radix Rhei Et Rhizome intervention in ICH was performed to complement and validate the results of systematic pharmacological predictions.

RESULTS

A total of three major networks were constructed in the present study: (1) compound-compound target network of Radix Rhei Et Rhizome, (2) DH-ICH PPI network, (3) proteomics proteins' PPI network. These three major networks have been analyzed by network topology, and several small networks derived (such as signaling pathway networks). The enrichment analysis showed that Radix Rhei Et Rhizome can intervene in several biological process (such as inflammation, smooth muscle proliferation, platelet activation, blood pressure regulation, angiogenesis, hypoxia, and inflammatory response of leukocytes), signaling pathway (such as FoxO signaling pathway, complement and coagulation cascades, cGMP-PKG signaling pathway, and Rap1 signaling pathway), and reactome pathway (such as signaling by interleukins, interleukin-4 and interleukin-13 signaling, nuclear receptor transcription pathway, and platelet activation).

CONCLUSION

Radix Rhei Et Rhizome may intervene in ICH-related biological process, signaling pathway, and reactome pathway found in this research so as to achieve the effect of treating ICH related injuries.

Vitamin D regulation of energy metabolism in cancer

Vitamin D exerts anti-cancer effects in recent clinical trials and preclinical models. The actions of vitamin D are primarily mediated through its hormonal form, 1,25-dihydroxyvitamin D (1,25(OH)₂ D). Previous literature describing in vitro studies has predominantly focused on the anti-tumourigenic effects of the hormone, such as proliferation and apoptosis. However, recent evidence has identified 1,25(OH)₂ D as a regulator of energy metabolism in cancer cells, where requirements for specific energy sources at different stages of progression are dramatically altered. The literature suggests that 1,25(OH)₂ D regulates energy metabolism, including glucose, glutamine and lipid metabolism during cancer progression, as well as oxidative stress protection, as it is closely associated with energy metabolism. Mechanisms involved in energy metabolism regulation are an emerging area in which vitamin D may inhibit multiple stages of cancer progression.

The metabolism of cancer cells during metastasis

Metastasis formation is the major cause of death in most patients with cancer. Despite extensive research, targeting metastatic seeding and colonization is still an unresolved challenge. Only recently, attention has been drawn to the fact that metastasizing cancer cells selectively and dynamically adapt their metabolism at every step during the metastatic cascade. Moreover, many metastases display different metabolic traits compared with the tumours from which they originate, enabling survival and growth in the new environment. Consequently, the stage-dependent metabolic traits may provide therapeutic windows for preventing or reducing metastasis, and targeting the new metabolic traits arising in established metastases may allow their eradication.

Streptomycin sulphate loaded solid lipid nanoparticles show enhanced uptake in macrophage, lower MIC in Mycobacterium and improved oral bioavailability

Present study addresses the challenge of incorporating hydrophilic streptomycin sulphate (STRS; log P -6.4) with high dose (1 g/day) into a lipid matrix of SLNs. Cold high-pressure homogenization technique used for SLN preparation achieved 30% drug loading and 51.17 ± 0.95% entrapment efficiency. Polyethylene glycol 600 as a supporting-surfactant assigned small size (218.1 ± 15.46 nm) and mucus-penetrating property. It was conceived to administer STRS-SLNs orally rather than intramuscularly. STRS-SLNs remained stable on incubation for varying times in SGF or SIF. STRS-SLNs were extensively characterised for microscopic (TEM and AFM), thermal (DSC), diffraction (XRD) and spectroscopic (NMR and FTIR) properties and showed zero-order controlled release. Enhanced (60 times) intracellular uptake was observed in THP-1 and Pgp expressing LoVo and DLD-1 cell lines, using fluorescein-SLNs. Presence of SLNs in LoVo cells was also revealed by TEM studies. STRS-SLNs showed 3 times reduction in MIC against Mycobacterium tuberculosis H37RV (256182) in comparison to free STRS. It also showed better activity against both M. bovis BCG and Mycobacterium tuberculosis H37RV (272994) in comparison to free STRS. Cytotoxicity and acute toxicity studies (OECD 425 guidelines) confirmed in vitro and in vivo safety of STRS-SLNs. Single-dose oral pharmacokinetic studies in rat plasma using validated LCMS/MS technique or the microbioassay showed significant oral absorption and bioavailability (160% - 710% increase than free drug).

Vascular-targeted micelles as a specific MRI contrast agent for molecular imaging of fibrin clots and cancer cells

Molecular medical imaging is intended to increase the accuracy of diagnosis, particularly in cardiovascular and cancer-related diseases, where early detection could significantly increase the treatment success rate. In this study, we present mixed micelles formed from four building blocks as a magnetic resonance imaging targeted contrast agent for the detection of atheroma and cancer cells. The building blocks are a gadolinium-loaded DOTA ring responsible for contrast enhancement, a fibrin-specific CREKA pentapeptide responsible for targeting, a fluorescent dye and DSPE-PEG₂₀₀₀. The micelles were fully characterized in terms of their size, zeta potential, stability, relaxivity and toxicity. Target binding assays performed on fibrin clots were quantified by fluorescence and image signal intensities and proved the binding power. An additional internalization assay showed that the micelles were also designed to specifically enter into cancer cells. Overall, these multimodal mixed micelles represent a potential formulation for MRI molecular imaging of atheroma and cancer cells.

The pleiotropic role of transcription factor STAT3 in oncogenesis and its targeting through natural products for cancer prevention and therapy

Signal transducer and activator of transcription 3 (STAT3) is one of the crucial transcription factors, responsible for regulating cellular proliferation, cellular differentiation, migration, programmed cell death, inflammatory response, angiogenesis, and immune activation. In this review, we have discussed the classical regulation of STAT3 via diverse growth factors, cytokines, G-protein-coupled receptors, as well as toll-like receptors. We have also highlighted the potential role of noncoding RNAs in regulating STAT3 signaling. However, the deregulation of STAT3 signaling has been found to be associated with the initiation and progression of both solid and hematological malignancies. Additionally, hyperactivation of STAT3 signaling can maintain the cancer stem cell phenotype by modulating the tumor microenvironment, cellular metabolism, and immune responses to favor drug resistance and metastasis. Finally, we have also discussed several plausible ways to target oncogenic STAT3 signaling using various small molecules derived from natural products.

Micronutrients and Breast Cancer Progression: A Systematic Review

Epidemiological studies on micronutrient consumption have reported protective associations in the incidence and/or progression of various cancer types. Supplementation with some of these micronutrients has been analyzed, showing chemoprotection, low toxicity, antiproliferation, and the ability to modify epigenetic signatures in various cancer models. This review investigates the reported effects of micronutrient intake or supplementation in breast cancer progression. A PubMed search was conducted with the keywords "micronutrients breast cancer progression", and the results were analyzed. The selected micronutrients were vitamins (C, D, and E), folic acid, metals (Cu, Fe, Se, and Zn), fatty acids, polyphenols, and iodine. The majority of in vitro models showed antiproliferative, cell-cycle arrest, and antimetastatic effects for almost all the micronutrients analyzed, but these effects do not reflect animal or human studies. Only one clinical trial with vitamin D and one pilot study with molecular iodine showed favorable overall survival and disease-free interval.

Calcitriol in the Presence of Conditioned Media from Metastatic Breast Cancer Cells Enhances Ex Vivo Polarization of M2 Alternative Murine Bone Marrow-Derived Macrophages

Simple Summary

In this study, we stimulated bone marrow-derived macrophages to M0, M1, and M2 subtypes, with or without calcitriol, or with or without 4T1 (metastatic), 67NR (non-metastatic), and Eph4-Ev (normal) cell culture supernatants (CMs) to test their effect on polarization. We showed that calcitriol increased the expression of Cd206 and Spp1 mRNA and CD36, CCL2, and arginase levels for M2 macrophages and decreased Cd80 and Spp1 mRNA and IL-1, IL-6, OPN, and iNOS for M1 macrophages. 4T1 CM influenced the expression of the studied genes and proteins to a greater extent than 67NR and Eph4; the strongest effect was noted for M2 macrophages. We show that calcitriol and 4T1 CM enhance the polarization of M2 macrophages and M2 macrophages differentiated with calcitriol-stimulated migration of 4T1 and 67NR cells. We indicate that the immunosuppressive properties of calcitriol may unfavorably affect the tumor microenvironment, and supplementation with vitamin D in oncological patients may not always bring benefits.

Abstract

In this study, we differentiated murine bone marrow-derived macrophages (BMDMs) into M0, M1, and M2 in the presence or absence of calcitriol. Real-time PCR analysis of gene expression, FACS analysis of surface markers, and chemokine/cytokine production assays were performed. In addition, the effect of the conditioned media (CM) from murine breast cancer 4T1 (metastatic) and 67NR (non-metastatic) and Eph4-Ev (normal) cells with and without calcitriol on the polarization of M1/M2 cells was determined. We found that calcitriol enhanced the differentiation of M2 macrophages, which was manifested by increased expression of Cd206 and Spp1 mRNA and CD36, Arg, and CCL2 in M2 BMDMs and by decreased expression of Cd80 and Spp1 mRNA and IL-1, IL-6, OPN, and iNOS in M1 BMDMs. 4T1 CM showed a higher effect on the gene and protein expression in macrophages than 67NR and Eph4-Ev, with the greatest effect observed on M2 macrophages which increased their differentiation and properties characteristic of alternative macrophages. Moreover, M2 macrophages differentiated with calcitriol-stimulated migration of 4T1 and 67NR cells through fibronectin and collagen type IV, respectively. Overall, our results indicated that vitamin D supplementation may not always be beneficial, especially in relation to cancers causing excessive, pathological activation of the immune system.

Potential of guggulsterone, a farnesoid X receptor antagonist, in the prevention and treatment of cancer

Cancer is one of the most dreadful diseases in the world with a mortality of 9.6 million annually. Despite the advances in diagnosis and treatment during the last couple of decades, it still remains a serious concern due to the limitations associated with currently available cancer management strategies. Therefore, alternative strategies are highly required to overcome these glitches. The importance of medicinal plants as primary healthcare has been well-known from time immemorial against various human diseases, including cancer. Commiphora wightii that belongs to Burseraceae family is one such plant which has been used to cure various ailments in traditional systems of medicine. This plant has diverse pharmacological properties such as antioxidant, antibacterial, antimutagenic, and antitumor which mostly owes to the presence of its active compound guggulsterone (GS) that exists in the form of Z- and E-isomers. Mounting evidence suggests that this compound has promising anticancer activities and was shown to suppress several cancer signaling pathways such as NF-κB/ERK/MAPK/AKT/STAT and modulate the expression of numerous signaling molecules such as the farnesoid X receptor, cyclin D1, survivin, caspases, HIF-1α, MMP-9, EMT proteins, tumor suppressor proteins, angiogenic proteins, and apoptotic proteins. The current review is an attempt to summarize the biological activities and diverse anticancer activities (both in vitro and in vivo) of the compound GS and its derivatives, along with its associated mechanism against various cancers.

Associations of TIMP-3 Genetic Polymorphisms with EGFR Statuses and Cancer Clinicopathologic Development in Lung Adenocarcinoma Patients

Lung adenocarcinoma (LADC) is a major subtype of lung cancer, particularly among populations of East Asia. The epidermal growth factor receptor (EGFR) is the most frequently mutated oncogene promoting LADC progression and can serve as a therapeutic target in LADC. The tissue inhibitor of metalloproteinases (TIMP)-3 is a major regulator of extracellular matrix turnover via targeting of matrix metalloproteinases (MMPs), and thus, plays a critical role in tumor development and progression. The purpose of this study was to investigate potential associations among TIMP-3 genetic polymorphisms, EGFR statuses, and cancer clinicopathologic development in patients with LADC. In this study, 277 LADC patients with different EGFR statuses were recruited to dissect the allelic discrimination of TIMP-3 -1296 T>C (rs9619311), TIMP3 249T>C (rs9862), and TIMP3 261C>T (rs11547635) polymorphisms using a TaqMan allelic discrimination assay. Our data showed that compared to those LADC patients with wild-type CC homozygotes of TIMP-3 rs9862, patients harboring TT homozygotes of rs9862 were at a higher risk of developing mutant EGFR (adjusted odds ratio (AOR) = 2.530; 95% confidence interval (CI): 1.230–5.205; p = 0.012), particularly the EGFR L858R point mutation (AOR = 2.975; 95% CI: 1.182–7.488; p = 0.021). Moreover, we observed that TIMP-3 TT homozygotes of rs9862 were correlated with the incidence of EGFR mutations in patients with a smoking habit (p = 0.045). Within male patients harboring a mutant EGFR, TIMP-3 rs9862 T (CT+TT) allele carriers were at higher risk of developing an advanced stage (p = 0.025) and lymph node metastasis (p = 0.043). Further analyses of clinical datasets revealed correlations of TIMP-3 expression with a favorable prognosis in patients with LADC. In conclusion, the data suggest that TIMP-3 rs9862 polymorphisms may contribute to identify subgroups of lung cancer patients at high risk for tumor progression, among carriers of LADC-bearing mutant EGFR.

Circular RNA hsa_circ_0000282 contributes to osteosarcoma cell proliferation by regulating miR-192/XIAP axis

Background

Circular RNAs (circRNAs) have emerged as a novel category of non-coding RNA, which exhibit a pivotal effect on regulating gene expression and biological functions, yet how circRNAs function in osteosarcoma (OSA) still demands further investigation. This study aimed at probing into the function of hsa_circ_0000282 in OSA.

Methods

The expressions of circ_0000282 and miR-192 in OSA tissues and cell lines were examined by quantitative real-time polymerase chain reaction (qRT-PCR), and the correlation between the expression level of circ_0000282 and clinicopathological features of OSA patients was analyzed. The expressions of X-linked inhibitor of apoptosis protein (XIAP), B-cell lymphoma-2 (Bcl-2) and Bcl-2 associated X protein (Bax) in OSA cells were assayed by Western blot. The proliferation and apoptosis of OSA cells were examined by CCK-8, BrdU and flow cytometry, respectively. Bioinformatics analysis, dual-luciferase reporter gene assay and RIP experiments were employed to predict and validate the targeting relationships between circ_0000282 and miR-192, and between miR-192 and XIAP, respectively.

Results

Circ_0000282 was highly expressed in OSA tissues and cell lines, which represented positive correlation with Enneking stage of OSA patients and negative correlation with tumor differentiation degree. In vitro experiments confirmed that overexpression of circ_0000282 markedly facilitated OSA cell proliferation and repressed cancer cell apoptosis in comparison to control group. Besides, knockdown of circ_0000282 repressed OSA cell proliferation and promoted apoptosis. Additionally, the binding relationships between circ_0000282 and miR-192, and between miR-192 and XIAP were validated. Circ_0000282 indirectly up-regulated XIAP expression by adsorbing miR-192, thereby playing a role in promoting cancer in OSA.

Conclusion

Circ_0000282 was a novel oncogenic circRNA in OSA. Circ_0000282/miR-192/XIAP axis regulated OSA cell proliferation apoptosis with competitive endogenous RNA mechanism.

MicroRNA-15b in extracellular vesicles from arsenite-treated macrophages promotes the progression of hepatocellular carcinomas by blocking the LATS1-mediated Hippo pathway

Arsenic, a human carcinogen, causes various human cancers, including those of the skin, lung, and liver. Hepatocellular carcinomas (HCCs), which have high mortality, are common malignancies worldwide. Tumor-associated macrophages (TAMs), which are considered to be similar to M2-polarized macrophages, promote tumor invasion and progression. Small non-coding RNAs (miRNAs) regulate expression of genes involved in progression of various malignancies. Extracellular vesicles (EVs), as mediators of cell communication, pass specific miRNAs directly from TAMs to tumor cells, promoting tumor pathogenesis and metastasis. In HCCs, large tumor suppressor kinase 1 (LATS1), functions as a tumor suppressor. However, the molecular mechanism by which miRNA modulates LATS1 expression in HCCs remains unclear. The results show that exposure to arsenite, increased miR-15b levels and induced M2 polarization of THP-1 cells. Elevated levels of miR-15b were transferred from arsenite-treated-THP-1 (As-THP-1) cells to HCC cells via miR-15b in EVs inhibited activation of the Hippo pathway by targeting LATS1, and was involved in promoting the proliferation, migration, and invasion of HCC cells. In conclusion, miR-15b in EVs from As-THP-1 cells is transferred to HCC cells, in which it targets and downregulates LATS1 expression and promotes the proliferation, migration, and invasion of HCC cells.

Anti-proliferative activity of A. Oxyphylla and its bioactive constituent nootkatone in colorectal cancer cells

Background

A. oxyphylla extract is known to possess a wide range of pharmacological activites. However, the molecular mechanism of A. oxyphylla and its bioactive compound nootkatone in colorectal cancer is unknown.

Methods

Our study aims to examine the role of A. oxyphylla and its bioactive compound nootkatone, in tumor suppression using several in vitro assays.

Results

Both A. oxyphylla extract and nootkatone exhibited antiproliferative activity in colorectal cancer cells. A. oxyphylla displayed antioxidant activity in colorectal cancer cells, likely mediated via induction of HO-1. Furthermore, expression of pro-apoptotic protein NAG-1 and cell proliferative protein cyclin D1 were increased and decreased respectively in the presence of A. oxyphylla. When examined for anticancer activity, nootkatone treatment resulted in the reduction of colony and spheroid formation. Correspondingly, nootkatone also led to increased NAG-1 expression and decreased cyclin D1 expression. The mechanism by which nootkatone suppresses cyclin D1 involves protein level regulation, whereas nootkatone increases NAG-1 expression at the transcriptional level. In addition to having PPARγ binding activity, nootkatone also increases EGR-1 expression which ultimately results in enhanced NAG-1 promoter activity.

Conclusion

In summary, our findings suggest that nootkatone is an anti-tumorigenic compound harboring antiproliferative and pro-apoptotic activity.

Possible applications of salvianolic acid B against different cancers

Cancer is the second death causing disease worldwide after cardiovascular abnormalities. The difficulty in treating tumor cells with more precise targeted interventions and recurrence of cancer after treatment may pose great difficulty in developing sustainable therapeutic regimens. These limitations have prompted the need to explore several compounds with ability to cease tumor growth while at the same time induce apoptosis of tumor cells. Several studies have emphasized the use of natural compounds as antitumor agents due to their high efficacy against cancer cells and low toxicity in normal cells. Salvianolic acid B (SAB), a naturally occurring phenolic compound extracted from the radix of Chinese herb Salvia miltiorrhiza can induce apoptosis in different types of tumor cells. It can be used to treat cardiovascular and neurodegenerative disorders, hepatic fibrosis, and cancers. Several studies have shown that SAB can mitigate tumorigenesis by modulating MAPK, PI3K/AKT, and NF-ĸB signaling pathways. It also sensitizes the tumor cells to different anti-cancer agents by reversing the multi-drug resistance mechanisms found in tumor cells. This review summarizes the studies showing antitumor potential of SAB in different types of cancer cell lines, animal models and highlights the possible mechanisms through which SAB can induce apoptosis, inhibit growth and metastasis in tumor cells. Moreover, the possible role of nano-technological approaches to induce targeted delivery of SAB to eradicate tumor cells has been also discussed.

Combined LIM kinase 1 and p21-Activated kinase 4 inhibitor treatment exhibits potent preclinical antitumor efficacy in breast cancer

LIM kinase 1 (LIMK1) and p21-activated kinase 4 (PAK4) are often over-expressed in breast tumors, which causes aggressive cancer phenotypes and unfavorable clinical outcomes. In addition to the well-defined role in regulating cell division, proliferation and invasion, the two kinases promote activation of the MAPK pathway and cause endocrine resistance through phosphorylating estrogen receptor alpha (ERα). PAK4 specifically phosphorylates LIMK1 and its functional partners, indicating possible value of suppressing both kinases in cancers that over-express PAK4 and/or LIMK1. Here, for the first time, we assessed the impact of combining LIMK1 inhibitor LIMKi 3 and PAK4 inhibitor PF-3758309 in preclinical breast cancer models. LIMK1 and PAK4 pharmacological inhibition synergistically reduced the survival of various cancer cell lines, exhibiting specific efficacy in luminal and HER2-enriched models, and suppressed development and ERα-driven signals in a BT474 xenograft model. In silico analysis demonstrated the cell lines with reliance on LIMK1 were the most prone to be susceptible to PAK4 inhibition. Double LIMK1 and PAK4 targeting therapy can be a successful therapeutic strategy for breast cancer, with a unique efficiency in the subtypes of luminal and HER2-enriched tumors.

Multidirectional Strategies for Targeted Delivery of Oncolytic Viruses by Tumor Infiltrating Immune Cells

Oncolytic virus (OV) immunotherapy has demonstrated to be a promising approach in cancer treatment due to tumor-specific oncolysis. However, their clinical use so far has been largely limited due to the lack of suitable delivery strategies with high efficacy. Direct 'intratumoral' injection is the way to cross the hurdles of systemic toxicity, while providing local effects. Progress in this field has enabled the development of alternative way using 'systemic' oncolytic virotherapy for producing better results. One major potential roadblock to systemic OV delivery is the low virus persistence in the face of hostile immune system. The delivery challenge is even greater when attempting to target the oncolytic viruses into the entire tumor mass, where not all tumor cells are equally exposed to exactly the same microenvironment. The microenvironment of many tumors is known to be massively infiltrated with various types of leucocytes in both primary and metastatic sites. Interestingly, this intratumoral immune cell heterogeneity exhibits a degree of organized distribution inside the tumor bed as evidenced, for example, by the hypoxic tumor microenviroment where predominantly recruits tumor-associated macrophages. Although in vivo OV delivery seems complicated and challenging, recent results are encouraging for decreasing the limitations of systemically administered oncolytic viruses and an improved efficiency of oncolytic viral therapy in targeting cancerous tissues in vitro. Here, we review the latest developments of carrier cell-based oncolytic virus delivery using tumor-infiltrating immune cells with a focus on the main features of each cellular vehicle.

Cancer and SOX proteins: New insight into their role in ovarian cancer progression/inhibition

Transcription factors are potential targets in disease therapy, particularly in cancer. This is due to the fact that transcription factors regulate a variety of cellular events, and their modulation has opened a new window in cancer therapy. Sex-determining region Y (SRY)-related high-mobility group (HMG) box (SOX) proteins are potential transcription factors that are involved in developmental processes such as embryogenesis. It has been reported that abnormal expression of SOX proteins is associated with development of different cancers, particularly ovarian cancer (OC). In the present review, our aim is to provide a mechanistic review of involvement of SOX members in OC. SOX members may suppress and/or promote aggressiveness and proliferation of OC cells. Clinical studies have also confirmed the potential of transcription factors as diagnostic and prognostic factors in OC. Notably, studies have demonstrated the relationship between SOX members and other molecular pathways such as ST6Ga1-I, PI3K, ERK and so on, leading to more complexity. Furthermore, SOX members can be affected by upstream mediators such as microRNAs, long non-coding RNAs, and so on. It is worth mentioning that the expression of each member of SOX proteins is corelated with different stages of OC. Furthermore, their expression determines the response of OC cells to chemotherapy. These topics are discussed in this review to shed some light on role of SOX transcription factors in OC.

Targeting gut barrier dysfunction with phytotherapies: Effective strategy against chronic diseases

The intestinal epithelial layer serves as a physical and functional barrier between the microbe-rich lumen and immunologically active submucosa; it prevents systemic translocation of microbial pyrogenic products (e.g. endotoxin) that elicits immune activation upon translocation to the systemic circulation. Loss of barrier function has been associated with chronic 'low-grade' systemic inflammation which underlies pathogenesis of numerous no-communicable chronic inflammatory disease. Thus, targeting gut barrier dysfunction is an effective strategy for the prevention and/or treatment of chronic disease. This review intends to emphasize on the beneficial effects of herbal formulations, phytochemicals and traditional phytomedicines in attenuating intestinal barrier dysfunction. It also aims to provide a comprehensive understanding of intestinal-level events leading to a 'leaky-gut' and systemic complications mediated by endotoxemia. Additionally, a variety of detectable markers and diagnostic criteria utilized to evaluate barrier improving capacities of experimental therapeutics has been discussed. Collectively, this review provides rationale for targeting gut barrier dysfunction by phytotherapies for treating chronic diseases that are associated with endotoxemia-induced systemic inflammation.

Napabucasin, a novel inhibitor of STAT3, inhibits growth and synergises with doxorubicin in diffuse large B-cell lymphoma

Diffuse large B-cell lymphoma (DLBCL), the most common type of aggressive non-Hodgkin lymphoma (NHL), has highly heterogeneous molecular characteristics. Although some patients initially respond to standard R-CHOP therapy, 30-40% develop refractory disease or suffer relapse. Signal transducer and activator of transcription 3 (STAT3), which regulates multiple oncogenic processes, has been found to be constitutively activated in various cancers, including DLBCL, suggesting its potential as a therapeutic target. In this study, we determined that 34% (23/69) of DLBCL patients expressed pSTAT3 (Y705) in tumour tissues. Napabucasin, a novel STAT3 inhibitor, exhibited potent cytotoxicity against NHL cell lines in a dose-dependent manner. Mechanistic studies demonstrated that napabucasin induced intrinsic and extrinsic cell apoptosis, downregulated the expression of STAT3 target genes, including the antiapoptotic protein Mcl-1, and regulated the ROS-mediated mitogen-activated protein kinase (MAPK) pathway. Most importantly, in vivo studies revealed the suppressive efficacy of napabucasin as a monotherapy without obvious toxicity. Furthermore, preliminary combination studies of napabucasin with doxorubicin showed significant synergism both in vitro and in vivo. Thus, our studies provide evidence that napabucasin alone or in combination is a promising therapeutic candidate for DLBCL patients.

1α,25(OH)2D3 Radiosensitizes Cancer Cells by Activating the NADPH/ROS Pathway

The radioresistance of tumors affect the outcome of radiotherapy. Accumulating data suggest that 1α,25(OH)₂D₃ is a potential anti-oncogenic molecule in various cancers. In the present study, we investigated the radiosensitive effects and underlying mechanisms of 1α,25(OH)₂D₃ in vitro and in vivo. We found that 1α,25(OH)₂D₃ enhanced the radiosensitivity of lung cancer and ovarian cancer cells by promoting the NADPH oxidase-ROS-apoptosis axis. Compared to the group that only received radiation, the survival fraction and self-renewal capacity of cancer cells treated with a combination of 1α,25(OH)₂D₃ and radiation were decreased. Both apoptosis and ROS were significantly increased in the combination group compared with the radiation only group. Moreover, N-acetyl-L-cysteine, a scavenger of intracellular ROS, reversed the apoptosis and ROS induced by 1α,25(OH)₂D₃, indicating that 1α,25(OH)₂D₃ enhanced the radiosensitivity of cancer cells in vitro by promoting ROS-induced apoptosis. Moreover, our results demonstrated that 1α,25(OH)₂D₃ promoted the ROS level via activating NADPH oxidase complexes, NOX4, p22^phox, and p47^phox. In addition, knockdown of the vitamin D receptor (VDR) abolished the radiosensitization of 1α,25(OH)₂D₃, which confirmed that 1α,25(OH)₂D₃ radiosensitized tumor cells that depend on VDR. Similarly, our study also evidenced that vitamin D₃ enhanced the radiosensitivity of cancer cells in vivo and extended the overall survival of mice with tumors. In summary, these results demonstrate that 1α,25(OH)₂D₃ enhances the radiosensitivity depending on VDR and activates the NADPH oxidase-ROS-apoptosis axis. Our findings suggest that 1α,25(OH)₂D₃ in combination with radiation enhances lung and ovarian cell radiosensitivity, potentially providing a novel combination therapeutic strategy.

Inflammatory Cells in Diffuse Large B Cell Lymphoma

Diffuse large B cell lymphoma (DLBCL), known as the most common non-Hodgkin lymphoma (NHL) subtype, is characterized by high clinical and biological heterogeneity. The tumor microenvironment (TME), in which the tumor cells reside, is crucial in the regulation of tumor initiation, progression, and metastasis, but it also has profound effects on therapeutic efficacy. The role of immune cells during DLBCL development is complex and involves reciprocal interactions between tumor cells, adaptive and innate immune cells, their soluble mediators and structural components present in the tumor microenvironment. Different immune cells are recruited into the tumor microenvironment and exert distinct effects on tumor progression and therapeutic outcomes. In this review, we focused on the role of macrophages, Neutrophils, T cells, natural killer cells and dendritic cells in the DLBCL microenvironment and their implication as target for DLBCL treatment. These new therapies, carried out by the induction of adaptive immunity through vaccination or passive of immunologic effectors delivery, enhance the ability of the immune system to react against the tumor antigens inducing the destruction of tumor cells.

A novel coordination complex of platinum (PT) induces cell death in colorectal cancer by altering redox balance and modulating MAPK pathway

Background

Colorectal cancer (CRC) is a heterogeneous tumor having various genetic alterations. The current treatment options had limited impact on disease free survival due to therapeutic resistance. Novel anticancer agents are needed to treat CRC specifically metastatic colorectal cancer. A novel coordination complex of platinum, (salicylaldiminato)Pt(II) complex with dimethylpropylene linkage (PT) exhibited potential anti-cancer activity. In this study, we explored the molecular mechanism of PT-induced cell death in colorectal cancer.

Methods

Colony formation was evaluated using the clonogenic assay. Apoptosis, cell cycle analysis, reactive oxygen species, mitochondrial membrane potential and caspase-3/− 7 were assessed by flow cytometry. Glutathione level was detected by colorimetric assay. PT-induced alteration in pro-apoptotic/ anti-apoptotic proteins and other signaling pathways were investigated using western blotting. P38 downregulation was performed using siRNA.

Results

In the present study, we explored the molecular mechanism of PT-mediated inhibition of cell proliferation in colorectal cancer cells. PT significantly inhibited the colony formation in human colorectal cancer cell lines (HT-29, SW480 and SW620) by inducing apoptosis and necrosis. This platinum complex was shown to significantly increase the reactive oxygen species (ROS) generation, depletion of glutathione and reduced mitochondrial membrane potential in colorectal cancer cells. Exposure to PT resulted in the downregulation of anti-apoptotic proteins (Bcl2, BclxL, XIAP) and alteration in Cyclins expression. Furthermore, PT increased cytochrome c release into cytosol and enhanced PARP cleavage leading to activation of intrinsic apoptotic pathway. Moreover, pre-treatment with ROS scavenger N-acetylcysteine (NAC) attenuated apoptosis suggesting that PT-induced apoptosis was driven by oxidative stress. Additionally, we show that PT-induced apoptosis was mediated by activating p38 MAPK and inhibiting AKT pathways. This was demonstrated by using chemical inhibitor and siRNA against p38 kinase which blocked the cytochrome c release and apoptosis in colorectal cancer cells.

Conclusion

Collectively, our data demonstrates that the platinum complex (PT) exerts its anti-proliferative effect on CRC by ROS-mediated apoptosis and activating p38 MAPK pathway. Thus, our findings reveal a novel mechanism of action for PT on colorectal cancer cells and may have therapeutic implication.

A brief overview of antitumoral actions of bruceine D

Cancer remains the second leading cause of mortality globally. In combating cancer, conventional chemotherapy and/or radiotherapy are administered as first-line therapy. However, these are usually accompanied with adverse side effects that decrease the quality of patient’s lives. As such, natural bioactive compounds have gained an attraction in the scientific and medical community as evidence of their anticancer properties and attenuation of side effects mounted. In particular, quassinoids have been found to exhibit a plethora of inhibitory activities such as anti-proliferative effects on tumor development and metastasis. Recently, bruceine D, a quassinoid isolated from the shrub Brucea javanica (L.) Merr. (Simaroubaceae), has come under immense investigation on its antineoplastic properties in various human cancers including pancreas, breast, lung, blood, bone, and liver. In this review, we have highlighted the antineoplastic effects of bruceine D and its mode of actions in different tumor models.

Goldenseal (Hydrastis canadensis L.) and its active constituents: A critical review of their efficacy and toxicological issues

Goldenseal (Hydrastis canadensis L.) is a medicinal plant widely used in various traditional systems of medicine and as a food supplement. It has been traditionally used by Native Americans as a coloring agent and as medicinal remedy for common diseases and conditions like wounds, digestive disorders, ulcers, skin and eye ailments, and cancer. Over the years, goldenseal has become a popular food supplement in the USA and other regions. The rhizome of this plant has been used for the treatment of a variety of diseases including, gastrointestinal disorders, ulcers, muscular debility, nervous prostration, constipation, skin and eye infections, cancer, among others. Berberine is one of the most bioactive alkaloid that has been identified in different parts of goldenseal. The goldenseal extract containing berberine showed numerous therapeutic effects such as antimicrobial, anti-inflammatory, hypolipidemic, hypoglycemic, antioxidant, neuroprotective (anti-Alzheimer's disease), cardioprotective, and gastrointestinal protective. Various research finding suggest the health promoting effects of goldenseal components and their extracts. However, few studies have also suggested the possible neurotoxic, hepatotoxic and phototoxic activities of goldenseal extract and its alkaloids. Thus, large randomized, double-blind clinical studies need to be conducted on goldenseal supplements and their main alkaloids to provide more evidence on the mechanisms responsible for the pharmaceutical activity, clinical efficacy and safety of these products. Thus, it is very important to review the scientific information about goldenseal to understand about the current scenario.