Glucose Metabolism in Cancer and Ischemia: Possible Therapeutic Consequences of the Warburg Effect

Cationic nanocarriers: A potential approach for targeting negatively charged cancer cell

Cancer, a widespread and lethal disease, necessitates precise therapeutic interventions to mitigate its devastating impact. While conventional chemotherapy remains a cornerstone of cancer treatment, its lack of specificity towards cancer cells results in collateral damage to healthy tissues, leading to adverse effects. Thus, the quest for targeted strategies has emerged as a critical focus in cancer research. This review explores the development of innovative targeting methods utilizing novel drug delivery systems tailored to recognize and effectively engage cancer cells. Cancer cells exhibit morphological and metabolic traits, including irregular morphology, unchecked proliferation, metabolic shifts, genetic instability, and a higher negative charge, which serve as effective targeting cues. Central to these strategies is the exploitation of the unique negative charge characteristic of cancer cells, attributed to alterations in phospholipid composition and the Warburg effect. Leveraging this distinct feature, researchers have devised cationic carrier systems capable of enhancing the specificity of therapeutic agents towards cancer cells. The review delineates the underlying causes of the negative charge in cancer cells and elucidates various targeting approaches employing cationic compounds for drug delivery systems. Furthermore, it delves into the methods employed for the preparation of these systems. Beyond cancer treatment, the review also underscores the multifaceted applications of cationic carrier systems, encompassing protein and peptide delivery, imaging, photodynamic therapy, gene delivery, and antimicrobial applications. This comprehensive exploration underscores the potential of cationic carrier systems as versatile tools in the fight against cancer and beyond.

Artematrolide A inhibited cervical cancer cell proliferation via ROS/ERK/mTOR pathway and metabolic shift

BACKGROUND

Artematrolide A (AR-A), a guaianolide dimer isolated from Artemisia atrovirens, demonstrated significant inhibitory effect on three human hepatoma cell lines (HepG2, Huh7 and SMMC7721). The anti-cervical cancer effect and mechanism of this compound have yet to be explored. This study is to reveal the role and mechanisms of artematrolide A on cervical cancer cells, and provide the pharmacological understanding of artematrolide A.

PURPOSE

To investigate the function and possible mechanism of artematrolide A on cervical cancer cells in vitro.

METHODS

HeLa S3 and SiHa cells were treated with artematrolide A at various concentrations. In this study, MTT, colony formation, cell migration and invasion, cell cycle analysis, cell apoptosis, reactive oxygen species (ROS) detection, western blotting, enzyme activity, and lactate production of artematrolide A were evaluated.

RESULTS

Artematrolide A inhibited cell viability, proliferation, migration and invasion in a dose-dependent manner, caused cell cycle arrest in G2/M phase, and induced cell apoptosis via Bcl-2/PARP-1. The mechanism of action of artematrolide A included two aspects: artematrolide A suppressed cell proliferation by activating ROS/ERK/mTOR signaling pathway and promoted glucose metabolism from aerobic glycolysis to mitochondrial respiration by activating pyruvate dehydrogenase complex (PDC) and oxoglutarate dehydrogenase complex (OGDC) via inhibiting the activity of alkaline phosphatases (ALP).

CONCLUSION

Artematrolide A exhibited a significant cytotoxic activity on cervical cancer cells, induced G2/M cell cycle arrest and apoptosis by activating ROS/ERK/mTOR signaling pathway and promoting metabolic shift from aerobic glycolysis to mitochondrial respiration, which suggested artematrolide A might be a potential agent for the treatment of cervical cancer.

WD-3 inhibits the proliferation of breast cancer cells by regulating the glycolytic pathway

Number 3 Prescription (WD-3) is an herbal remedy used in traditional Chinese medicine that has been shown to improve the outcomes of patients with advanced colon and gastric cancers. This study aimed to investigate the effect of WD-3 on proliferation, glycolysis, and hexokinase 2 expression in breast cancer cells. Four breast cancer cell lines (MDA-MB-231, BT-549, MCF-7, and MCF-7/ADR-RES) were treated with different concentrations of WD-3 compared with blank control (phosphate-buffered saline). Each of the breast cancer cell lines was also divided into WD-3, paclitaxel, and blank control group. Cell proliferation and morphology were assessed by MTT assay, nuclear Hoechst 33258 staining, or immunofluorescence. Apoptosis was analyzed by flow cytometry. High performance liquid chromatography was used for measurement of ATP, ADP, and AMP. Hexokinase 2 expression was analyzed by Western blot and quantitative reverse transcription PCR. WD-3 inhibited proliferation and increased apoptosis in all four breast cancer cell lines, in a dose-dependent manner. ATP and EC (energy charge) were significantly decreased in WD-3-treated BT-549 and MDA-MB-231 cells. WD-3 significantly downregulated the protein and mRNA expression of hexokinase II in BT-549 cells, however, not in the other three breast cancer cell lines. Our findings indicate that WD-3 targets the glycolytic pathway in breast cancer cells to exert its antitumor activity.

Drp1 regulates mitochondrial dysfunction and dysregulated metabolism in ischemic injury via Clec16a-, BAX-, and GSH- pathways

The adaptation of mitochondrial homeostasis to ischemic injury is not fully understood. Here, we studied the role of dynamin-related protein 1 (Drp1) in this process. We found that mitochondrial morphology was altered in the early stage of ischemic injury while mitochondrial dysfunction occurred in the late stage of ischemia. Drp1 appeared to inhibit mitophagy by upregulating mito-Clec16a, which suppressed mito-Parkin recruitment and subsequently impaired the formation of autophagosomes in vascular tissues after ischemic injury. Moreover, ischemia-induced Drp1 activation enhanced apoptosis through inducing mitochondrial translocation of BAX and thereby increasing release of Cytochrome C to activate caspase-3/-9 signalling. Furthermore, Drp1 mediated metabolic disorders and inhibited the levels of mitochondrial glutathione to impair free radical scavenging, leading to further increases in ROS and the exacerbation of mitochondrial dysfunction after ischemic injury. Together, our data suggest a critical role for Drp1 in ischemic injury.

Histone Butyrylation/ Acetylation Remains Unchanged in Triple Negative Breast Cancer Cells after a Long Term Metabolic Reprogramming

Background:

Altered metabolism is one of the hallmarks of the cancer cells which reciprocally interrelate with epigenetic processes, such as post-translational histone modifications to maintain their desired gene expression profiles. The role of beta-hydroxybutyrate as a ketone body in cancer cell biology and histone modifications are reported. The present study aimed to evaluate the impacts of long-term metabolic reprogramming via glucose restriction and beta-hydroxybutyrate treatment on histone acetylation and butyrylation in MDA-MB231 cells as a model of triple negative stem-like breast cancer.

Methods:

For long-term treatment, cells were set up in three groups receiving DMEM with restricted glucose (250 mg/L), DMEM with restricted glucose but enriched with five millimolar beta-hydroxybutyrate and DMEM with standard glucose (1g\L) and investigated for a month. Histone modifications, including H3 acetylation and butyrylation, were investigated by immunoblotting after an acid extraction of the histone proteins.

Results and Conclusion:

Neither beta-hydroxybutyrate enrichment nor glucose restriction elicited a significant effect on the butyrylation or acetylation level of histone H3 upon a long-term treatment. Metabolic plasticity of cancer cells, mainly stem-like triple negative breast cancer cells alleviate or neutralize the impact of long-term metabolic reprogramming via restriction of glucose and histone modifications enrichment. These results shed new light upon the mechanism of controversial efficacy of ketogenic diets in clinical trials.

Hexokinase II Upregulation Contributes to Asiaticoside-Induced Protection of H9c2 Cardioblasts During Oxygen-Glucose Deprivation/Reoxygenation

Asiaticoside (AS), one of the main functional components of Centella asiatica, has been reported to protect neurons from ischemia-hypoxia-induced injury. However, the role of AS in myocardial oxygen-glucose deprivation/reoxygenation (OGD/R) injury has not been investigated. The aim of this study was to investigate the role of AS in OGD/R-treated H9c2 cardiomyocytes and the underlying mechanism involved. Cell viability was detected using MTT assay. Cell apoptosis was measured using flow cytometry. The oxidative stress was assessed by detecting the malonaldehyde (MDA) content and activities of superoxide dismutase, glutathione peroxidase, and catalase (CAT). The glucose consumption and lactate production were determined to reflect glycolysis rate. The expression levels of hexokinase II (HK2) were detected using reverse transcription quantitative polymerase chain reaction and Western blot. H9c2 cells were transfected with small interfering RNA targeting HK2 (si-HK2) to knockdown HK2. Results showed that AS improved cell viability and inhibited apoptosis in OGD/R-injured H9c2 cells. AS pretreatment prevented OGD/R-induced oxidative stress, as evidenced by the decreased MDA content, and increased activities of superoxide dismutase, glutathione peroxidase, and CAT. The decreased glucose consumption and lactate production in OGD/R-injured H9c2 cells were reversed after AS treatment. Mechanically, AS induced the expression of HK2 in OGD/R-injured H9c2 cells. Knockdown of HK2 abolished the protective effects of AS on OGD/R-injured H9c2 cells. In conclusion, the protective effects of AS on cardiomyocytes from OGD/R-induced injury were mediated at least partly by upregulating HK2.

Challenges and perspectives in the treatment of diabetes associated breast cancer

Type 2 diabetes mellitus is one of the most common chronic disease worldwide and affects all cross-sections of the society including children, women, youth and adults. Scientific evidence has linked diabetes to higher incidence, accelerated progression and increased aggressiveness of different cancers. Among the different forms of cancer, research has reinforced a link between diabetes and the risk of breast cancer. Some studies have specifically linked diabetes to the highly aggressive, triple negative breast cancers (TNBCs) which do not respond to conventional hormonal/HER2 targeted interventions, have chances of early recurrence, metastasize, tend to be more invasive in nature and develop drug resistance. Commonly used anti-diabetic drugs, such as metformin, have recently gained importance in the treatment of breast cancer due to their proposed anti-cancer properties. Here we discuss the link between diabetes and breast cancer, the metabolic disturbances in diabetes that support the development of breast cancer, the challenges involved and future perspective and directions. We link the three main metabolic disturbances (dyslipidemia, hyperinsulinemia and hyperglycemia) that occur in diabetes to potential aberrant molecular pathways that may lead to the development of an oncogenic phenotype of the breast tissue, thereby leading to acceleration of cell growth, proliferation, migration, inflammation, angiogenesis, EMT and metastasis and inhibition of apoptosis in breast cancer cells. Furthermore, managing diabetes and treating cancer using a combination of anti-diabetic and classical anti-cancer drugs should prove to be more efficient in the treatment diabetes associated cancers.

Image-guided chemistry altering biology: An in vivo study of thermoembolization

RATIONALE

Advances in image-guided drug delivery for liver cancer have shown a significant survival benefit. However, incomplete treatment is common and residual disease is often found in explanted liver specimens. In addition, the need to treat a malignancy from multiple mechanisms at the same time for optimal outcomes is becoming more widely appreciated. To address this, we hypothesized that an exothermic chemical reaction could be performed in situ. Such a strategy could in principle combine several angles of attack, including ischemia, hyperthermia, acidic protein denaturation, and metabolic modulation of the local environment.

METHODS

The University of Texas MD Anderson Cancer Center Institutional Animal Care and Use Committee approved this study. Outbred swine (25-35 kg, 5 control and 5 experimental) were treated under general anesthesia. Embolization was performed with coaxial microcatheter technique in a segmental hepatic arterial branch using either ethiodized oil as control or with thermoembolic solutionBlood samples were obtained before, immediately after, and the day following the procedure just before CT scans and euthanasia. Livers were explanted and samples were obtained for histologic analysis.

RESULTS

All animals survived the procedure and laboratory values of the control and experimental groups remained within normal limits. The control group had a diffuse or cloudy pattern of attenuation on follow-up CT scan the day after, consistent with gradual antegrade sinusoidal transit of the embolic material. The experimental group had clearly defined vascular casts with some degree of peripheral involvement. At histology, the control group samples had the appearance of normal liver, whereas the experimental group had coagulative necrosis in small pale, punctate areas extending several hundred microns away from the treated vessels and a brisk inflammatory response just outside the margins.

CONCLUSION

In situ chemistry via thermoembolization shows early promise as a fundamentally new tactic for image-guided therapy of solid tumors.

First In Vivo Test of Thermoembolization: Turning Tissue Against Itself Using Transcatheter Chemistry in a Porcine Model

PURPOSE

Embolotherapies are commonly used for management of primary liver cancer. Explant studies of treated livers, however, reveal an untreated tumor in a high fraction of cases. To improve on this, we propose a new concept referred to as thermoembolization. In this technique, the embolic material reacts in local tissues. Highly localized heat energy is released simultaneously with the generation of acid in the target vascular bed. Combined with ischemia, this should provide a multiplexed attack. We report herein our initial results testing the feasibility of this method in vivo.

MATERIALS AND METHODS

Institutional approval was obtained, and three outbred swine were treated in a segmental hepatic artery branch (right or left medial lobe) with thermoembolic material (100, 400, or 500 µL). Solutions (2 or 4 mol/L) of an acid chloride were made using ethiodized oil as the vehicle. Animals were housed overnight, scanned by CT, and euthanized. Necropsy samples of treated tissue were obtained for histologic analysis.

RESULTS

All animals survived the procedure. Vascular stasis occurred rapidly in all cases despite the small volumes used. The lower concentration (2 mol/L) penetrated more distally than the 4 mol/L solution. At CT the following day, vascular casts of ethiodized oil were observed, indicating recanalization had not occurred. Histology specimens demonstrated coagulative necrosis centered on the vessel lumen extending for several hundred microns with a peripheral inflammatory infiltrate.

CONCLUSIONS

Thermoembolization is a new technique for embolization with initial promise. However, results indicate much work must be done to optimize the technique.

Attenuation of miR-34a protects cardiomyocytes against hypoxic stress through maintenance of glycolysis

MiRNAs are a class of endogenous, short, single-stranded, non-coding RNAs, which are tightly linked to cardiac disorders such as myocardial ischemia/reperfusion (I/R) injury. MiR-34a is known to be involved in the hypoxia-induced cardiomyocytes apoptosis. However, the molecular mechanisms are unclear. In the present study, we demonstrate that under low glucose supply, rat cardiomyocytes are susceptible to hypoxia. Under short-time hypoxia, cellular glucose uptake and lactate product are induced but under long-time hypoxia, the cellular glucose metabolism is suppressed. Interestingly, an adaptive up-regulation of miR-34a by long-time hypoxia was observed both in vitro and in vivo, leading to suppression of glycolysis in cardiomyocytes. We identified lactate dehydrogenase-A (LDHA) as a direct target of miR-34a, which binds to the 3′-UTR region of LDHA mRNA in cardiomyocytes. Moreover, inhibition of miR-34a attenuated hypoxia-induced cardiomyocytes dysfunction through restoration of glycolysis. The present study illustrates roles of miR-34a in the hypoxia-induced cardiomyocytes dysfunction and proposes restoration of glycolysis of dysfunctional cardiomyocytes by inhibiting miR-34a during I/R might be an effectively therapeutic approach against I/R injury.