Side Effects in Cancer Therapy: Are Sphingolipids to Blame?

AI-2 quorum sensing controlled delivery of cytolysin-A by tryptophan auxotrophic low-endotoxic Salmonella and its anticancer effects in CT26 mice with colon cancer

INTRODUCTION

The limitations of conventional cancer therapies necessitate target-oriented, highly invasive, and safe treatment approaches. Hence, the intrinsic anti-tumor activity of Salmonella can offer better options to combat cancers.

OBJECTIVES

This study aims to utilize attenuated Salmonella and deliver cytolytic protein cytolysin A (ClyA) under quorum sensing (QS) signaling for precise localized expression in tumors but not in healthy organs.

METHODS

The therapeutic delivery strain was imposed with tryptophan auxotroph for selective colonization in tumors by trpA and trpE deletion, and lipid-A and O-antigen were altered by pagL and rfaL deletions using lambda red recombination method. The strain was transformed with the designed QS-controlled ClyA expression vector which was validated by western blot. The in vivo passaged therapeutic strain was used for treatment four times at a weekly interval, with a dose of 5 × 106 CFU/mouse for cancer therapy.

RESULTS

The attenuated strain induced minimal endotoxicity-related cytokines TNF-α, IL-1β, and IFN-γ and exhibited adequate colonization despite earlier exposure in mice. The QS-controlled ClyA expression was confirmed by western blot from bacterial cultures grown at different cell densities. The results demonstrated that the in vivo passaged strain preferentially colonized the tumor after vacating the spleen, liver, and lung, leaving no outward histological scars. The anti-cancer effect of the designed construct was evaluated in the murine CT26 colon cancer model. The expression of ClyA increased tumoricidal activity by 67 % compared to vector control.

CONCLUSION

Hence, the anti-tumor effect of the engineered Salmonella strain was improved by ClyA expression via QS activation after achieving the threshold bacterial cell density. Further, immunohistochemical staining of the tumor and other organs corroborated the QS-controlled tumor-specific expression of ClyA. Overall, the results imply that the developed anti-cancer Salmonella has low endotoxicity and QS-controlled expression of ClyA as beneficial safety elements and supports recurrent Salmonella inoculation by O-antigen deficiency.

A cuproptosis-related lncRNA signature for predicting prognosis and immunotherapy response of lung adenocarcinoma

BACKGROUND

Copper-induced cell death (cuproptosis) is a new regulatory cell death mechanism. Long noncoding RNAs (lncRNAs) are related to tumor immunity and metastasis. However, the correlation of cuproptosis-related lncRNAs with the immunotherapy response and prognosis of lung adenocarcinoma (LUAD) patients is not clear.

METHODS

We obtained the clinical characteristics and transcriptome data from TCGA-LUAD dataset (containing 539 LUAD and 59 paracancerous tissues). By utilizing LASSO-penalized Cox regression analysis, we identified a prognostic signature composed of cuproptosis-related lncRNAs. This signature was then utilized to segregate patients into two different risk categories based on their respective risk scores. The identification of differentially expressed genes (DEGs) between high- and low-risk groups was carried out using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses. We evaluated the immunotherapy response by analyzing tumor mutational burden (TMB), immunocyte infiltration and Tumor Immune Dysfunction and Exclusion (TIDE) web application. The "pRRophetic" R package was utilized to conduct further screening of potential therapeutic drugs for their sensitivity.

RESULTS

We ultimately identified a prognostic risk signature that includes six cuproptosis-related lncRNAs (AP003778.1, AC011611.2, CRNDE, AL162632.3, LY86-AS1, and AC090948.1). Compared with clinical characteristics, the signature was significantly correlated with prognosis following the control of confounding variables (HR = 2.287, 95% CI = 1.648-3.174, p ˂ 0.001), and correctly predicted 1-, 2-, and 3-year overall survival (OS) rates (AUC value = 0.725, 0.715, and 0.662, respectively) in LUAD patients. In terms of prognosis, patients categorized as low risk exhibited more positive results in comparison to those in the high-risk group. The enrichment analysis showed that the two groups had different immune signaling pathways. Immunotherapy may offer a more appropriate treatment option for high-risk patients due to their higher TMB and lower TIDE scores. The higher risk score may demonstrate increased sensitivity to bexarotene, cisplatin, epothilone B, and vinorelbine.

CONCLUSIONS

Based on cuproptosis-related lncRNAs, we constructed and validated a novel risk signature that may be used to predict immunotherapy efficacy and prognosis in LUAD patients.

Orobanche crenata Forssk. Extract Affects Human Breast Cancer Cell MCF-7 Survival and Viral Replication

BACKGROUND

Breast cancer (BC) is the leading cause of death worldwide. The severity of BC strictly depends on the molecular subtype. The less aggressive hormone-positive subtype is treated with adjuvant endocrine therapy (AET), which causes both physical and psychological side effects. This condition strongly impacts the adherence and persistence of AET among oncologic patients. Moreover, viral infections also constitute a serious problem for public health. Despite their efficacy, antiviral agents present several therapeutic limits. Accordingly, in the present work, we investigated the antitumor and antiviral activities of Orobanche crenata Forssk. (O. crenata), a parasitic plant, endemic to the Mediterranean basin, traditionally known for its beneficial properties for human health.

METHODS

The MTT assay was carried out to evaluate the cytotoxic effect of O. crenata leaf extract (OCLE) on human breast cancer cells (MCF-7 and MDA-MB-231) and the primary HFF-1 cell line. The lactic dehydrogenase (LDH) assay was performed on MCF-7 cells to analyze necrotic cell death. The antioxidant effect of OCLE was evaluated by intracellular determination of the reactive oxygen species and thiol groups, by DPPH and ABTS assays. The antiviral activity of OCLE was determined against Poliovirus 1, Echovirus 9, Human respiratory syncytial virus, Adenovirus type 2 and type 5, Coxsackievirus B1 (CoxB1) and B3 (CoxB3), Herpes simplex type 1 (HSV-1) and type 2 (HSV-2), and β-Coronavirus by the plaque reduction assay.

RESULTS

The extract, after 24 h of incubation, did not affect MDA-MB-231 and HFF-1 cell viability. However, at the same time point, it showed a dose-dependent inhibitory effect on MCF-7 cells, with an increase in LDH release. OCLE exhibited free radical scavenging activity and significantly increased non-protein thiol levels in MCF-7 cells. OCLE effectively inhibited HSV-1, HSV-2, CoxB1, and CoxB3 replication.

CONCLUSIONS

The overall results showed an interesting inhibitory effect of OCLE on both MCF-7 cell survival and viral replication.

Sphingolipids and Lymphomas: A Double-Edged Sword

Lymphomas are a highly heterogeneous group of hematological neoplasms. Given their ethiopathogenic complexity, their classification and management can become difficult tasks; therefore, new approaches are continuously being sought. Metabolic reprogramming at the lipid level is a hot topic in cancer research, and sphingolipidomics has gained particular focus in this area due to the bioactive nature of molecules such as sphingoid bases, sphingosine-1-phosphate, ceramides, sphingomyelin, cerebrosides, globosides, and gangliosides. Sphingolipid metabolism has become especially exciting because they are involved in virtually every cellular process through an extremely intricate metabolic web; in fact, no two sphingolipids share the same fate. Unsurprisingly, a disruption at this level is a recurrent mechanism in lymphomagenesis, dissemination, and chemoresistance, which means potential biomarkers and therapeutical targets might be hiding within these pathways. Many comprehensive reviews describing their role in cancer exist, but because most research has been conducted in solid malignancies, evidence in lymphomagenesis is somewhat limited. In this review, we summarize key aspects of sphingolipid biochemistry and discuss their known impact in cancer biology, with a particular focus on lymphomas and possible therapeutical strategies against them.

CK1 Is a Druggable Regulator of Microtubule Dynamics and Microtubule-Associated Processes

Protein kinases of the Casein Kinase 1 family play a vital role in the regulation of numerous cellular processes. Apart from functions associated with regulation of proliferation, differentiation, or apoptosis, localization of several Casein Kinase 1 isoforms to the centrosome and microtubule asters also implicates regulatory functions in microtubule dynamic processes. Being localized to the spindle apparatus during mitosis Casein Kinase 1 directly modulates microtubule dynamics by phosphorylation of tubulin isoforms. Additionally, site-specific phosphorylation of microtubule-associated proteins can be related to the maintenance of genomic stability but also microtubule stabilization/destabilization, e.g., by hyper-phosphorylation of microtubule-associated protein 1A and RITA1. Consequently, approaches interfering with Casein Kinase 1-mediated microtubule-specific functions might be exploited as therapeutic strategies for the treatment of cancer. Currently pursued strategies include the development of Casein Kinase 1 isoform-specific small molecule inhibitors and therapeutically useful peptides specifically inhibiting kinase-substrate interactions.

Risk for relapse and death after adjuvant chemotherapy associated with SNPs in patients with breast cancer - A retrospective study

For the women breast cancer (BC) patients included in this retrospective study, the first line of systemic treatment in adjuvant modality for breast cancer (BC) after surgery was fluorouracil, epirubicin and cyclophosphamide (FEC). The aim of our investigation was to analyze the prognostic biomarkers for relapse and death of patients eight to ten years after chemotherapy in association with nausea and vomiting.

METHOD

This retrospective study included 114 patients treated between 2010 and 2013. Blood samples for Single Nucleotide Polymorphism (SNP) analysis before the chemotherapy treatment were collected. The medical records were used to determine relapses and death.

RESULTS

Sixteen percent relapsed and 9 % died during the follow-up period. SNPs located in the genes ESR and CASP9 were associated with both relapse and death.

CONCLUSIONS

Relapse and death were at a relative moderate level and consistent with other studies. Two SNPs in the Estrogen hormone receptor gene ESR1 and the apoptosis execution gene Caspases 9 (Casp9) were found to be associated with a higher risk of relapse and death. These findings suggest the possible value of blood biomarkers in the selection of individual treatments in the clinical setting.

Protective Effect of Polysaccharides Extracted from Cudrania tricuspidata Fruit against Cisplatin-Induced Cytotoxicity in Macrophages and a Mouse Model

Although cisplatin is one of most effective chemotherapeutic drugs that is widely used to treat various types of cancer, it can cause undesirable damage in immune cells and normal tissue because of its strong cytotoxicity and non-selectivity. This study was conducted to investigate the cytoprotective effects of Cudrania tricuspidata fruit-derived polysaccharides (CTPS) against cisplatin-induced cytotoxicity in macrophages, lung cancer cell lines, and a mouse model, and to explore the possibility of application of CTPS as a supplement for anticancer therapy. Both cisplatin alone and cisplatin with CTPS induced a significant cytotoxicity in A549 and H460 lung cancer cells, whereas cytotoxicity was suppressed by CTPS in cisplatin-treated RAW264.7 cells. CTPS significantly attenuated the apoptotic and necrotic population, as well as cell penetration in cisplatin-treated RAW264.7 cells, which ultimately inhibited the upregulation of Bcl-2-associated X protein (Bax), cytosolic cytochrome c, poly (adenosine diphosphateribose) polymerase (PARP) cleavage, and caspases-3, -8, and -9, and the downregulation of B cell lymphoma-2 (Bcl-2). The CTPS-induced cytoprotective action was mediated with a reduction in reactive oxygen species production and mitochondrial transmembrane potential loss in cisplatin-treated RAW264.7 cells. In agreement with the results obtained above, CTPS induced the attenuation of cell damage in cisplatin-treated bone marrow-derived macrophages (primary cells). In in vivo studies, CTPS significantly inhibited metastatic colonies and bodyweight loss as well as immunotoxicity in splenic T cells compared to the cisplatin-treated group in lung metastasis-induced mice. Furthermore, CTPS decreased the level of CRE and BUN in serum. In summation, these results suggest that CTPS-induced cytoprotective action may play a role in alleviating the side effects induced by chemotherapeutic drugs.

Current methodologies to refine bioavailability, delivery, and therapeutic efficacy of plant flavonoids in cancer treatment

Over the last two decades, several advancements have been made to improve the therapeutic efficacy of plant flavonoids, especially in cancer treatment. Factors such as low bioavailability, poor flavonoid stability and solubility, ineffective targeted delivery, and chemo-resistance hinder the application of flavonoids in anti-cancer therapy. Many anti-cancer compounds failed in the clinical trials because of unexpected altered clearance of flavonoids, poor absorption after administration, low efficacy, and/or adverse effects. Hence, the current research strategies are focused on improving the therapeutic efficacy of plant flavonoids, especially by enhancing their bioavailability through combination therapy, engineering gut microbiota, regulating flavonoids interaction with adenosine triphosphate binding cassette efflux transporters, and efficient delivery using nanocrystal and encapsulation technologies. This review aims to discuss different methodologies with examples from reported dietary flavonoids that showed an enhanced anti-cancer efficacy in both in vitro and in vivo models. Further, the review discusses the recent progress in biochemical modifications of flavonoids to improve bioavailability, solubility, and therapeutic efficacy.

Antibacterial, Anticandidal, Phytochemical, and Biological Evaluations of Pellitory Plant

Pellitory plant (Parietaria judaica (PJ)) is one of the most widely used Arabian traditional medicinal plants due to its ability to cure several infectious diseases and other illnesses. The current study is aimed at assessing the phytoconstituents, antilipase, antiamylase, antimicrobial, and cytotoxic characters of the Pellitory plant (Parietaria judaica (PJ)). Phytochemical screening and procyanidin detection were conducted according to the standard phytochemical procedures. Porcine pancreatic lipase and α-amylase inhibitory activities were carried out using p-nitrophenyl butyrate and dinitrosalicylic acid assays, respectively. In addition, antimicrobial activity was determined utilizing a microdilution assay against several bacterial and fungal strains. Besides, the cytotoxic effect against HeLa cell line was tested employing 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium (MTS) assay. The quantitative test results revealed that the methanol fraction of PJ contains 18.55 ± 0.55 mg of procyanidin and has a potential α-amylase inhibitory activity compared with the antidiabetic drug Acarbose with IC₅₀ values of 15.84 ± 2.25 and 28.18 ± 1.22 μg/ml, respectively. Also, it has a potential antilipase activity compared to the commercial antiobesity drug, Orlistat, with IC₅₀ values of 38.9 ± 0.29 and 12.3 ± 0.35 μg/ml, respectively. The acetone, hexane, and methanol fractions have broad-spectrum antibacterial activity against the screened bacterial strains, while the acetone fraction has shown anticandidal activity with a MIC value of 0.195 mg/ml. The PJ hexane and acetone fractions decreased HeLa cell viability significantly (p value < 0.0001) by approximately 90% at the concentration of 0.625 mg/ml. The revealed outcomes showed that the methanol fraction has strong α-amylase and lipase inhibitory characters. Besides, acetone, hexane, and methanol fractions have broad-spectrum antibacterial activity, while the acetone fraction revealed potent antifungal activity against Candida albicans. Moreover, at low concentrations, hexane and acetone fractions have potent cytotoxic and antiproliferative activity against HeLa cancer cells. Nevertheless, PJ acetone, hexane, and methanol fractions can serve as an effective source of natural products to develop new antiobesity, antidiabetic, antimicrobial, and anticancer agents.

Anticancer property of ginsenoside Rh2 from ginseng

Ginseng has been used as a well-known traditional Chinese medicine since ancient times. Ginsenosides as its main active constituents possess a broad scope of pharmacological properties including stimulating immune function, enhancing cardiovascular health, increasing resistance to stress, improving memory and learning, developing social functioning and mental health in normal persons, and chemotherapy. Ginsenoside Rh2 (Rh2) is one of the major bioactive ginsenosides from Panax ginseng. When applied to cancer treatment, Rh2 not only exhibits the anti-proliferation, anti-invasion, anti-metastasis, induction of cell cycle arrest, promotion of differentiation, and reversal of multi-drug resistance activities against multiple tumor cells, but also alleviates the side effects after chemotherapy or radiotherapy. In the past decades, nearly 200 studies on Rh2 in the treatment of cancer have been published, however no specific reviews have been conducted by now. So the purpose of this review is to provide a systematic summary and analysis of the anticancer effects and the potential mechanisms of Rh2 extracted from Ginseng then give a future prospects about it. In the end of this paper the metabolism and derivatives of Rh2 also have been documented.

Role of 1-Deoxysphingolipids in docetaxel neurotoxicity

A major dose-limiting side effect of docetaxel chemotherapy is peripheral neuropathy. Patients' symptoms include pain, numbness, tingling and burning sensations, and motor weakness in the extremities. The molecular mechanism is currently not understood, and there are no treatments available. Previously, we have shown an association between neuropathy symptoms of patients treated with paclitaxel and the plasma levels of neurotoxic sphingolipids, the 1-deoxysphingolipids (1-deoxySL) (Kramer et al, FASEB J, 2015). 1-DeoxySL are produced when the first enzyme of the sphingolipid biosynthetic pathway, serine palmitoyltransferase (SPT), uses L-alanine as a substrate instead of its canonical amino acid substrate, L-serine. In the current investigation, we tested whether 1-deoxySL accumulate in the nervous system following systemic docetaxel treatment in mice. In dorsal root ganglia (DRG), we observed that docetaxel (45 mg/kg cumulative dose) significantly elevated the levels of 1-deoxySL and L-serine-derived ceramides, but not sphingosine-1-phosphate (S1P). S1P is a bioactive sphingolipid and a ligand for specific G-protein-coupled receptors. In the sciatic nerve, docetaxel decreased 1-deoxySL and ceramides. Moreover, we show that in primary DRG cultures, 1-deoxysphingosine produced neurite swellings that could be reversed with S1P. Our results demonstrate that docetaxel chemotherapy up-regulates sphingolipid metabolism in sensory neurons, leading to the accumulation of neurotoxic 1-deoxySL. We suggest that the neurotoxic effects of 1-deoxySL on axons can be reversed with S1P.

Response of preantral follicles exposed to quinoxaline: A new compound with anticancer potential

The culture of preantral follicles as an in vitro model to evaluate the toxicity of new anticancer drug has being established. Therefore, the aim of this study was to evaluate the effect of quinoxaline derivative the 2 2- (XYZC 6H 3 -CH=N-NH)-quinoxaline, 1 (QX) on caprine preantral follicles. We evaluate the follicular morphology and activation, proliferation and apoptosis of granulosa cells and finally the protein (ABCB1) and genes expression (cyclin/Cdks), respectively involved in multidrug resistance and cell cycle progression. Ovarian fragments containing primordial and developing follicles were exposed (in vitro culture) to different concentrations of QX (QX1.5, QX3.0 or QX6.0 μM/mL) during 6 days. To evaluate the effect of QX, the ovarian tissue was exposed to Paclitaxel 0.1 μg/mL (PTX - negative control) or in culture media without QX (MEM). At the end of exposure time, we realized that the QX (all concentrations) increased (P < .05) the normal morphology of preantral follicles compared to control (not treated ovarian tissue) or MEM. However, QX6.0 showed a enhanced (P < .05) on follicular activation (burnout) and apoptosis than QX1.5 and QX3.0. Expression of ABCB1 was similar between QX1.5 and QX6.0 and both were lower than control, MEM and PTX. Interestingly, the apoptosis rate in QX3.0 was similar to control and MEM and lower then QX1.5; QX6.0 and PTX. We conclude that quinoxaline may be a promising chemotherapeutic agent, however, other concentrations within a defined range (2-5.5 μM) could be widely investigated.