L-arginine/5-fluorouracil combination treatment approaches cells selectively: Rescuing endothelial cells while killing MDA-MB-468 breast cancer cells

L-arginine combination with 5-fluorouracil inhibit hepatocellular carcinoma cells through suppressing iNOS/NO/AKT-mediated glycolysis

L-arginine can produce nitric oxide (NO) under the action of inducible nitric oxide synthase (iNOS), while 5-fluorouracil (5-FU) can induce the increase of iNOS expression. The present study was to investigate the mechanism of L-arginine combined with 5-FU regulating glucose metabolism of hepatocellular carcinoma (HCC) through iNOS/NO/AKT pathway. The combination of L-arginine and 5-FU resulted in decreased cell survival and exhibited synergistic cytotoxic effects in HepG2 and SMMC7721 cells. Meanwhile, L-arginine increased 5-FU inhibitory effect on HepG2 and SMMC7721 cells by increasing NO production. Co-treatment with L-arginine and 5-FU resulted in a significant decrease in both G6PDH and LDH enzymatic activities, as well as reduced levels of ATP and LD compared to treatment with L-arginine or 5-FU alone. Moreover, the combination of L-arginine and 5-FU resulted in a decrease in the expression of GLUT1, PKM2, LDHA, p-PI3K and p-AKT. Furthermore, the combination demonstrated a synergistic effect in downregulating the expression of HIF-1α and β-catenin, which were further diminished upon the addition of shikonin, a specific inhibitor of PKM2. LY294002 treatment further reduced the expression of GLUT1, PKM2, and LDHA proteins induced by combined L-arginine and 5-FU treatment compared to the combined group. However, the reduction in p-PI3K, p-AKT, and GLUT1 expression caused by L-arginine and 5-FU combination was also reversed in HepG2 and SMMC7721 cells with iNOS knockdown, respectively. Additionally, the combination of L-arginine and 5-FU led to a greater reduction in the enzymatic activity of ALT, AST, G6PDH and LDH, as well as a significant reduction in hepatic index, AFP, AFP-L3, ATP and LD levels in a rat model of HCC. Moreover, the simultaneous administration of L-arginine and 5-FU significantly improved the gross morphology of the liver, reduced nuclear atypia, inhibited the proliferation of cancer cells, and decreased the expression levels of p-PI3K, p-AKT, GLUT1, PKM2, and LDHA, while iNOS expression was increased in the combination group. Taking together, L-arginine and 5-FU combination resulted in the inhibition of enzymes in aerobic glycolysis via the iNOS/NO/AKT pathway, which led to the suppression of glucose metabolism and downregulation of nuclear transcription factors, thereby impeding the proliferation of hepatocellular carcinoma cells.

Fibroblasts mediate endothelium response to angiogenic cues in a newly developed 3D stroma engineered model

Three-dimensional stroma engineered models would enable fundamental and applicative studies of human tissues interaction and remodeling in both physiological and pathological conditions. In this work, we propose a 3D vascularized stroma model to be used as in vitro platform for drug testing. A pullulan/dextran-based porous scaffold containing pre-patterned microchannels of 100 μm diameter is used for co-culturing of fibroblasts within the matrix pores and endothelial cells to form the lumen. Optical clearing of the constructs by hyperhydration allows for in-depth imaging of the model up to 1 mm by lightsheet and confocal microscopy. Our 3D vascularized stroma model allows for higher viability, metabolism and cytokines expression compared to a monocultured vascular model. Stroma-endothelium cross-talk is then investigated by exposing the system to pro and anti-angiogenic molecules. The results highlight the protective role played by fibroblasts on the vasculature, as demonstrated by decreased cytotoxicity, restoration of nitric oxide levels upon challenge, and sustained expression of endothelial markers CD31, vWF and VEGF. Our tissue model provides a 3D engineered platform for in vitro studies of stroma remodeling in angiogenesis-driven events, known to be a leading mechanism in diseased conditions, such as metastatic cancers, retinopathies and ischemia, and to investigate related potential therapies.

Reassessing vascular endothelial growth factor (VEGF) in anti-angiogenic cancer therapy

Vascularization is fundamental to the growth and spread of tumor cells to distant sites. As a consequence, angiogenesis, the sprouting of new blood vessels from existing ones, is a characteristic trait of cancer. In 1971, Judah Folkman postulated that tumour growth is angiogenesis dependent and that by cutting off blood supply, a neoplastic lesion could be potentially starved into remission. Decades of research have been devoted to understanding the role that vascular endothelial growth factor (VEGF) plays in tumor angiogenesis, and it has been identified as a significant pro-angiogenic factor that is frequently overexpressed within a tumor mass. Today, anti-VEGF drugs such as Sunitinib, Sorafenib, Axitinib, Tanibirumab, and Ramucirumab have been approved for the treatment of advanced and metastatic cancers. However, anti-angiogenic therapy has turned out to be more complex than originally thought. The failure of this therapeutic option calls for a reevaluation of VEGF as the major target in anti-angiogenic cancer therapy. The call for reassessment is based on two rationales: first, tumour blood vessels are abnormal, disorganized, and leaky; this not only prevents optimal drug delivery but it also promotes hypoxia and metastasis; secondly, tumour growth or regrowth might be blood vessel dependent and not angiogenesis dependent as tumour cells can acquire blood vessels via non-angiogenic mechanisms. Therefore, a critical assessment of VEGF, VEGFRs, and their inhibitors could glean newer options such as repurposing anti-VEGF drugs as vascular normalizing agents to enhance drug delivery of immune checkpoint inhibitors.

5-Fluorouracil, capecitabine and vasospasm: a scoping review of pathogenesis, management options and future research considerations

BACKGROUND

5-Fluorouracil (5-FU) is a widely used chemotherapeutic agent that can cause cardiotoxicity manifesting, among others, as chest pain. Capecitabine is an oral prodrug of 5-FU, with reported preferential activation in malignant cells that may also cause cardiotoxic reactions. Standard treatment of 5-FU and capecitabine induced chest pain with vasodilators is mostly effective, but there are several cases of patients unresponsive to these agents.

METHODS

We performed a PubMed search on 31st May 2020. We used a three keyword search strategy using Boolean search operators. More specifically, we included fluorouracil or 5-FU or capecitabine and chest pain or angina and mechanism or treatment or management. We included primary reports of clinical and non-clinical data, as well as systematic reviews. Narrative reviews, expert opinions, letters to the editor and other forms of non-primary literature were excluded.

RESULTS

Our search yielded a total of 1595 reports. Of these, 1460 were narrative reviews or irrelevant to the topic and were excluded. A total of 135 reports were used for our review. We used 81 reports for data extraction, which included 13 clinical trials, 4 retrospective reports, 61 case reports, and 3 systematic reviews.

CONCLUSION

We report the incidence and predisposing factors, the value of available diagnostic procedures, and standard medical and invasive treatments. We also speculate on the potential benefit of arginine as a promising option both in prevention as well as treatment of 5-FU-induced chest pain. Finally, gaps of evidence are identified and proposals are made in terms of future research.

Baicalin; a promising chemopreventive agent, enhances the antitumor effect of 5-FU against breast cancer and inhibits tumor growth and angiogenesis in Ehrlich solid tumor

Despite considerable advances in cancer treatment, chemotherapy remains a cornerstone in breast cancer therapy. Therefore, reducing chemoresistance and adverse effects of chemotherapy is a priority. In this regard, Baicalin (BA) is the dominant natural flavonoid extracted from the roots of Scutellaria baicalensis showed fascinating antitumor activity in many types of cancers, including breast cancer. The present study aimed to explore the chemopreventive and antitumor action of baicalin alone and in combination with 5-FU in addition to its ability to enhance the antitumor effect of 5-FU on breast cancer using the Ehrlich solid tumor-mice model.

MATERIALS AND METHODS

A total of 70 female mice were divided into seven groups (1st group, saline group; 2nd group, DMSO group; 3rd group, BA+EST group; 4th group, EST group; 5th group, EST+5-FU; 6th group, EST+BA group; 7th group, EST+5-FU+BA).tumors were assessed by weight and histopathological examination. Inflammation, angiogenesis, and apoptosis were examined by ELISA, qRT-PCR, and immunohistochemical examinations.

RESULTS

showed that pre-treatment with baicalin and treatment with baicalin and/or 5-FU significantly reduced inflammation and angiogenesis indicated by suppression of NF-kB/ IL-1β and VEGF amplification loop with marked elevation in apoptosis indicated by up-regulation of apoptotic caspase-3, pro-apoptotic p53, Bax and downregulation of anti-apoptotic Bcl-2.

CONCLUSION

BA is a promising preventive or adjuvant therapy in breast cancer treatment with 5-FU mainly via cooperative inhibition of inflammation, angiogenesis, and triggering apoptotic cell death.

Protective Effect of Quercetin Nanoemulsion on 5-Fluorouracil-Induced Oral Mucositis in Mice

The target of this study was to evaluate the efficacy, histopathological, oxidative stress, and molecular effects of quercetin (QRC) in mice with oral mucositis induced by 5-fluorouracil (5-FU). Thirty-six albino male mice with oral mucositis induced by 5-FU as a chemotherapeutic agent were used in this study. The animals were randomly divided into 6 groups: control group, mucositis (MUC) group, pretreatment group, posttreatment group, and two last groups including nanoemulsion form of QRC with a dose of 5 mg/kg in both pretreatment and posttreatment. In the present evaluation, fewer oral lesions were observed in the QRC posttreatment groups compared to the pretreatment and nanoemulsion receiving groups. In the SOD assay, the most significant difference was observed in the posttreatment nanogroup (41.073 ± 1.24) and pretreatment nanogroup (43.453 ± 2.60) in comparison to the 5-FU group (30.897 ± 1.93). The results of CAT assay also showed a significant difference in nano-posttreatment (124.60 ± 10.85), posttreatment (135.4 ± 9.82), and nano-pretreatment groups (128.80 ± 7.20) compared to the 5-FU group (55.07 ± 8.91). The expression of inflammatory genes such as Hif-1α and NfκB in this group was lower than in the other groups, although this difference was not significant. It seems that the use of QRC can improve the treatment process of oral mucositis induced by 5-FU.

Hypoxia: A key feature of COVID-19 launching activation of HIF-1 and cytokine storm

COVID-19, disease caused by the new coronavirus, SARS-CoV-2, appeared in the end of 2019 and was rapidly spread in most countries. This respiratory virus has different symptoms from moderate to severe, and results in lung pneumonia following acute respiratory distress syndrome (ARDS) and patient’s death in severe cases. ARDS is a severe form of acute lung injury that is caused by high inflammatory response of the innate immunity cells. Hypoxia is the common feature in the inflammatory sites with having various impacts on this condition by induction of some factors such as hypoxia inducible factor-1α (HIF-1α). HIF-1α regulates some important cellular processes including cell proliferation, metabolism and angiogenesis. Furthermore, this factor is activated during the immune responses and plays important roles in the inflammation site by inducing pro-inflammatory cytokines production through immune cells. So, in this study the possible effect of the HIF-1α on the COVID-19 pathogenesis with emphasizes on its role on innate immunity response has been discussed.

Clinical effects of curcumin in enhancing cancer therapy: A systematic review

BACKGROUND

Curcumin is herbal compound that has been shown to have anti-cancer effects in pre-clinical and clinical studies. The anti-cancer effects of curcumin include inhibiting the carcinogenesis, inhibiting angiogenesis, and inhibiting tumour growth. This study aims to determine the Clinical effects of curcumin in different types of cancers using systematic review approach.

METHODS

A systematic review methodology is adopted for undertaking detailed analysis of the effects of curcumin in cancer therapy. The results presented in this paper is an outcome of extracting the findings of the studies selected from the articles published in international databases including SID, MagIran, IranMedex, IranDoc, Google Scholar, ScienceDirect, Scopus, PubMed and Web of Science (ISI). These databases were thoroughly searched, and the relevant publications were selected based on the plausible keywords, in accordance with the study aims, as follows: prevalence, curcumin, clinical features, cancer.

RESULTS

The results are derived based on several clinical studies on curcumin consumption with chemotherapy drugs, highlighting that curcumin increases the effectiveness of chemotherapy and radiotherapy which results in improving patient's survival time, and increasing the expression of anti-metastatic proteins along with reducing their side effects.

CONCLUSION

The comprehensive systematic review presented in this paper confirms that curcumin reduces the side effects of chemotherapy or radiotherapy, resulting in improving patients' quality of life. A number of studies reported that, curcumin has increased patient survival time and decreased tumor markers' level.

Kaempferol protects mitochondria and alleviates damages against endotheliotoxicity induced by doxorubicin

Kaempferol (Kae), a flavonoid, has been found in fruits and other vegetables, possesses many biological activities. 14-3-3 protein exerts protection on various types of injured tissues and cells. Doxorubicin (Dox) causes excessive reactive oxygen species (ROS) generation, which induces endotheliotoxicity and cardiotoxicity. We hypothesized that Kae could protect vascular endothelium by regulating 14-3-3γ or related pathways against Dox toxicity. HUVECs were established Dox-toxic injury models. Kae's effects were assessed with many physiological, enzymatic, cellular, and molecular biological indexes. Our results showed that Dox-induced damage in HUVECs were reduced through Kae to promote the expression of total protein 14-3-3γ and mitochondrial Bcl-2, phosphorylate Bad, increase cell viability, NO content, DDAHⅡactivity, p-eNOS/eNOS ratio, and MMP levels, maintained NAD⁺/NADH and GSH/GSSG balance, and decrease LDH and caspase-3 activities, ADMA content, ROS generation, mPTP openness, and apoptosis. Kae's effects were abolished with pAD/14-3-3γ-shRNA downregulating 14-3-3γ expression, or ABT-737 inhibiting Bcl-2 activity. This study demonstrated that Kae protected the vascular endothelium against Dox-induced damage by regulating 14-3-3γ and ADMA/DDAHⅡ/eNOS/NO pathway, inhibiting oxidative stress, and improving mitochondrial function.

Tetramethylpyrazine alleviates iron overload damage in vascular endothelium via upregulating DDAHII expression

Iron overload causes vascular endothelium damage. It has been thought to relate excessive reactive oxygen species (ROS) generation. Tetramethylpyrazine (TMP), an active ingredient of Ligusticum chuanxiong Hort, protects various cells by inhibiting oxidative stress and cascade reaction of apoptosis. However, whether TMP can increase DDAHII activity and expression against endothelial cell damage induced by iron overload, and the protective mechanism has not been elucidated. In this study, 50 μM iron dextran and 25 μM TMP were used to co-treat HUVECs for 48 h. TMP could increase cell viability and decrease LDH activity, enhance DDAHII expression and activity, p-eNOS/eNOS ratio, NO content, and reduce ADMA level. TMP also showed a strong antioxidant activity with inhibited ROS generation and oxidative stress. Moreover, TMP attenuated mitochondrial membrane potential loss, inhibited mitochondrial permeability transition pore openness, and decreased apoptosis induced by iron overload. While mentioned above, the protective effects of TMP were abolished with the addition of pAD/DDAHII-shRNA. The effects of TMP against iron overload were similar to the positive control groups, L-arginine, a competitive substrate of ADMA, or edaravone, free radical scavenger. These results signify that TMP alleviated iron overload damage in vascular endothelium via ROS/ADMA/ DDAHII/eNOS/NO pathway.

TSGA10 Over Expression Decreases Metastasic and Metabolic Activity by Inhibiting HIF-1 in Breast Cancer Cells

BACKGROUND AND AIMS

HIF-1 is an important factor that play critical roles in metabolic and metastasis activity of cancer cells. HIF-1 activity can have regulated by TSGA10. Although decreased metastatic activity of cancer cells through TSGA10 inhibitory effect on HIF-1 have already been demonstrated, changes in cancer metabolism and its impact on metastasis in breast cancer is still not determined. So, we aimed to investigate TSGA10 overexpression effect on breast cancer metabolism as well as metastasis.

METHODS

TSGA10 vector was designed and stable transfected into MCF-7 cells. The efficiency of transfection was assessed by Real-time PCR and western blot. After HIF-1 induction at high and low glucose conditions, cell proliferation, cell cycle profile, metabolic and metastasis activity of cells were assessed. Furthermore, biomarker expressions of ER, PR, HER2, Ki67 and E-cadherin in cancer cells were measured.

RESULTS

Our results showed decrease of cell proliferation and cell cycle arrest in G2/M phase. Reduce expression of GLUT1, lactate production and reactive oxygen species (ROS) below their basal level indicated decreased metabolic activity. Furthermore, metastatic activity reduction was shown by decrease expression of different involve genes in metastasis, protelytic activity of MMOLP-2/9, carbonic anhydrase (CA) IX activity and increase of wound closure. Moreover, except for E-cadherin, expression of ER, PR, HER2 and Ki67 was declined in cells.

CONCLUSION

Our findings indicated that TSGA10 overexpression could decrease the metastatic and metabolic activity of cancer cells through its inhibitory effect on HIF-1 activity. Therefore, TSGA10 could be considered in the research for therapeutic candidates in cancer.

TSGA10 overexpression inhibits angiogenesis of HUVECs: A HIF-2α biased perspective

Testis-specific gene antigen 10 (TSGA10) is a protein overexpressed in most cancers; except for some certain types where its expression is reduced. TSGA10 overexpression in HeLa cells has been shown to disrupt hypoxia inducible factor-1α (HIF-1α) axis and exert potent inhibitory effects. Since HIF-1α is structurally and biochemically similar to HIF-2α, TSGA10 is expected to bind HIF-2α and inhibit its function as well. This study elucidated that increased expression of TSGA10 in manipulated human umbilical vein endothelial cells (HUVECs) decreased the proliferation and migration of these cells as affirmed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and wound healing tests, respectively. It also inhibited in vitro angiogenesis of these cells in 3D collagen-cytodex model. Expression levels of genes controlled by HIF-2α including autocrine vascular endothelial growth factor (VEGF) were also assessed using real-time PCR. Our bioinformatic analysis also showed that TSGA10 could bind HIF-2α. Moreover, flow cytometry results indicated a cell cycle arrest in G2/M. Therefore, this study showed that overexpression of TSGA10, as a tumor suppressor gene, in endothelial cells resulted in decreased proliferation, migration and therefore, angiogenic activity of HUVECs. Since angiogenesis is vital for tumor development and metastasis, our findings could be of clinical significance in cancer therapy.