Curcumin induces apoptosis and inhibits proliferation in infantile hemangioma endothelial cells via downregulation of MCL-1 and HIF-1α

Mechanism of the HIF-1α/VEGF/VEGFR-2 pathway in the proliferation and apoptosis of human haemangioma endothelial cells

Haemangiomas (HAs) are prevalent vascular endothelial cell tumours. With respect to the possible involvement of HIF-1α in HAs, we have explored its role in haemangioma endothelial cell (HemEC) proliferation and apoptosis. shRNA HIF-1α and pcDNA3.1 HIF-α were manipulated into HemECs. HIF-α, VEGF, and VEGFR-2 mRNA and protein levels were assessed by qRT-PCR and Western blotting. Cell proliferation and viability, cell cycle and apoptosis, migration and invasion, and ability to form tubular structures were assessed by colony formation assay, CCK-8, flow cytometry, Transwell assay, and tube formation assay. Cell cycle-related protein levels, and VEGF and VEGFR-2 protein interaction were detected by Western blot and immunoprecipitation assays. An Haemangioma nude mouse model was established by subcutaneous injection of HemECs. Ki67 expression was determined by immunohistochemical staining. HIF-1α silencing suppressed HemEC neoplastic behaviour and promoted apoptosis. HIF-1α facilitated VEGF/VEGFR-2 expression and the VEGF had interacted with VEGFR-2 at protein - protein level. HIF-1α silencing arrested HemECs at G0/G1 phase, diminished Cyclin D1 protein level, and elevated p53 protein level. VEGF overexpression partially abrogated the effects of HIF-1α knockdown on inhibiting HemEC malignant behaviours. Inhibiting HIF-1α in nude mice with HAs repressed tumour growth and Ki67-positive cells. Briefly, HIF-1α regulated HemEC cell cycle through VEGF/VEGFR-2, thus promoting cell proliferation and inhibiting apoptosis.

Single or Daily Application of Topical Curcumin Prevents Ultraviolet B-Induced Apoptosis in Mice

Curcumin is a natural ingredient with antioxidant effects, widely studied as a treatment for various types of cancer. However, its effects on ultraviolet radiation have not been fully explored. The effects of single or daily application of 0.1-100 μM curcumin on cell apoptosis in ultraviolet B (UVB)-induced mice were tested using an experimental double-blind posttest design with a control group and two research models: a single application of curcumin before a single UVB exposure and daily application of curcumin for 7 days before a single UVB exposure on the seventh day. Apoptotic cells were counted using a tunnel system kit. The number of apoptotic cells under a single or daily application of curcumin for 7 days was significantly lower than that of the UVB controls (p ≤ 0.05). The number of apoptotic cells decreased with the increasing concentration of curcumin, and the maximum effect was observed at 100 μM. Daily application of topical curcumin was superior in preventing apoptosis (mean apoptotic cell count of 14.86 ± 1.68) compared with a single application (17.46 ± 0.60; p = 0.011). Topical curcumin can act as a potential photoprotective agent in preventing cutaneous malignancies due to UVB radiation. Further studies are warranted, especially in humans.

Ranugha PS, Seetharam KA. IADVL SIG pediatric dermatology (academy) recommendations on Hemangioma of Infancy (HOI)

Hemangioma of infancy (HOI) is a benign vascular proliferation. Though resolution is the norm, potential complications make an accurate diagnosis and early management of importance. The Indian association of dermatologists, venereologists and leprologists (IADVL) special interest group (SIG) paediatric dermatology in association with IADVL academy did an extensive analysis of the literature on the clinical features, diagnosis, and management of HOI published between 2010 and 2021. Online meetings were conducted from February 2021 to March 2022 to reach a consensus on these recommendations which are made from an Indian perspective.

Vernonia amygdalina Delile Induces Apoptotic Effects of PC3 Cells: Implication in the Prevention of Prostate Cancer

Background

Prostate cancer (PCa) is one of the common cancers in males and its incidence keeps increasing globally. Approximately 81% of PCa is diagnosed during the early stage of the disease. The treatment options for prostate care include surgery, radiotherapy, and chemotherapy, but these treatments often have side effects that may lead to issues such as impotence or decreased bowel function. Our central goal is to test the apoptotic effects of Vernonia amygdalina Delile (an edible medicinal plant that is relatively inexpensive, nontoxic, and virtually without side effects) for the prevention of PCa using human adenocarcinoma (PC-3) cells as a test model.

Methods

To address our central goal, PC-3 cells were treated with Vernonia amygdalina Delile (VAD). Cell cycle arrest and cell apoptosis were evaluated by Flow Cytometry assessment. Nucleosomal DNA fragmentation was detected by agarose gel electrophoresis.

Results

Flow cytometry data showed that VAD induced cell cycle arrest at the G0/G1 checkpoint and significantly upregulated caspase-3 in treated cells compared to the control cells. Agarose gel electrophoresis resulted in the formation of DNA ladders in VAD-treated cells.

Conclusions

These results suggest that inhibition of cancer cell growth, induction of cell cycle arrest, and apoptosis through caspase-3 activation and nucleosomal DNA fragmentation are involved in the therapeutic mechanisms of VAD as a candidate drug towards the prevention and/or treatment of PCa.

Curcumin: reclaiming the lost ground against cancer resistance

Curcumin, a polyphenol, has a wide range of biological properties such as anticancer, antibacterial, antitubercular, cardioprotective and neuroprotective. Moreover, the anti-proliferative activities of Curcumin have been widely studied against several types of cancers due to its ability to target multiple pathways in cancer. Although Curcumin exhibited potent anticancer activity, its clinical use is limited due to its poor water solubility and faster metabolism. Hence, there is an immense interest among researchers to develop potent, water-soluble, and metabolically stable Curcumin analogs for cancer treatment. While drug resistance remains a major problem in cancer therapy that renders current chemotherapy ineffective, curcumin has shown promise to overcome the resistance and re-sensitize cancer to chemotherapeutic drugs in many studies. In the present review, we are summarizing the role of curcumin in controlling the proliferation of drug-resistant cancers and development of curcumin-based therapeutic applications from cell culture studies up to clinical trials.

Antioxidant and Cytoprotective Properties of Polyphenol-Rich Extracts from Antirhea borbonica and Doratoxylon apetalum against Atherogenic Lipids in Human Endothelial Cells

The endothelial integrity is the cornerstone of the atherogenic process. Low-density lipoprotein (LDL) oxidation occurring within atheromatous plaques leads to deleterious vascular effects including endothelial cell cytotoxicity. The aim of this study was to evaluate the vascular antioxidant and cytoprotective effects of polyphenol-rich extracts from two medicinal plants from the Reunion Island: Antirhea borbonica (A. borbonica), Doratoxylon apetalum (D. apetalum). The polyphenol-rich extracts were obtained after dissolving each dry plant powder in an aqueous acetonic solution. Quantification of polyphenol content was achieved by the Folin–Ciocalteu assay and total phenol content was expressed as g gallic acid equivalent/100 g plant powder (GAE). Human vascular endothelial cells were incubated with increasing concentrations of polyphenols (1–50 µM GAE) before stimulation with oxidized low-density lipoproteins (oxLDLs). LDL oxidation was assessed by quantification of hydroperoxides and thiobarbituric acid reactive substances (TBARS). Intracellular oxidative stress and antioxidant activity (catalase and superoxide dismutase) were measured after stimulation with oxLDLs. Cell viability and apoptosis were quantified using different assays (MTT, Annexin V staining, cytochrome C release, caspase 3 activation and TUNEL test). A. borbonica and D. apetalum displayed high levels of polyphenols and limited LDL oxidation as well as oxLDL-induced intracellular oxidative stress in endothelial cells. Polyphenol extracts of A. borbonica and D. apetalum exerted a protective effect against oxLDL-induced cell apoptosis in a dose-dependent manner (10, 25, and 50 µM GAE) similar to that observed for curcumin, used as positive control. All together, these results showed significant antioxidant and antiapoptotic properties for two plants of the Reunion Island pharmacopeia, A. borbonica and D. apetalum, suggesting their therapeutic potential to prevent cardiovascular diseases by limiting LDL oxidation and protecting the endothelium.

Evaluation and Characterization of Curcumin-β-Cyclodextrin and Cyclodextrin-Based Nanosponge Inclusion Complexation

Cyclodextrin polymers and cyclodextrin-based nanosponges have been widely investigated for increasing drug bioavailability. This study examined curcumin's complexation stability and solubilization with β-cyclodextrin and β-cyclodextrin-based nanosponge. Nanosponges were prepared through the cross-linking of β-cyclodextrin with different molar ratios of diphenyl carbonate. Phase solubility experiments were conducted to evaluate the formed complexes and evaluate the potential of using β-cyclodextrin and nanosponge in pharmaceutical formulations. Furthermore, physicochemical characterizations of the prepared complexes included PXRD, FTIR, NMR, and DSC. In addition, in vitro release studies were performed for the prepared formulations. The formation of β-cyclodextrin complexes enhanced curcumin solubility up to 2.34-fold compared to the inherent solubility, compared to a 2.95-fold increment in curcumin solubility when loaded in β-cyclodextrin-based nanosponges. Interestingly, the stability constant for curcumin nanosponges was (4972.90 M^-1), which was ten times higher than that for the β-cyclodextrin complex, where the value was 487.34 M^-1. The study results indicated a decrease in the complexation efficiency and solubilization effect with the increased cross-linker amount. This study's findings showed the potential of using cyclodextrin-based nanosponge and the importance of studying the effect of cross-linking density for the preparation of β-cyclodextrin-based nanosponges to be used for pharmaceutical formulations.

Curcumin as a great contributor for the treatment and mitigation of colorectal cancer

Cancer is one of the life-taking diseases worldwide and among cancer-related death; colorectal cancer is the third most. Though conventional methods of treatment are available, multidrug resistance and side effects are predominant. Physicians and scientists are working side by side to develop an effective medicament, which is safe and cost-effective. However, most failures are obtained when focused on the clinical perspective. This review mainly brings out the correlation between the curcumin and its use for the mitigation of colorectal cancer, the use of curcumin as a chemotherapeutic agent, chemosensitizer, and in a combination and synergistic approach. The pharmacokinetics and pharmacodynamics properties of curcumin and its formulation approach helps in giving an idea to develop new approaches for the treatment of colorectal cancer using curcumin.

Silencing long non‑coding RNA NEAT1 suppresses the tumorigenesis of infantile hemangioma by competitively binding miR‑33a‑5p to stimulate HIF1α/NF‑κB pathway

Infantile hemangioma (IH) is one of the most common vascular tumors that occurs during childhood, but its pathogenesis is currently not completely understood. Even though lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) plays vital roles in tumorigenesis of malignant tumors, its roles in IH remain unclear. Therefore, we evaluate the function of lncRNA NEAT1 in IH. Reverse transcription-quantitative PCR indicated that IH tissues exhibited high expression levels of NEAT1 and hypoxia-inducible factor 1α (HIF1α), and low expression levels of the microRNA (miR)-33a-5p. Small interfering RNA-mediated depletion of NEAT1 suppressed hemangioma endothelial cell (HemEC) proliferation, migration and invasion. The data suggested that NEAT1 positively regulated HIF1α expression by sponging miR-33a-5p in HemECs. miR-33a-5p overexpression or HIF1α silencing also acted to suppress HemEC proliferation, migration and invasion. Furthermore, the results indicated that the NEAT1/miR-33a-5p/HIF1α axis regulated the NF-κB signaling pathway. Collectively, the results revealed that depletion of lncRNA NEAT1 suppressed the tumorigenesis of IH by competitively binding miR-33a-5p and thereby stimulating the HIF1α/NF-κB signaling pathway.

Knockdown of KRT17 decreases osteosarcoma cell proliferation and the Warburg effect via the AKT/mTOR/HIF1α pathway

Keratins are fibrous structural proteins that serve essential roles in forming the stratum corneum and protect the cells in this layer of skin from damage. Keratin 17 (KRT17) is a key member of the keratins, and dysregulated expression of KRT17 has been reported in various types of cancer, such as lung and gastric cancer. The present study aimed to identify the role of KRT17 in osteosarcoma and the underlying molecular mechanism. The expression of KRT17 in osteosarcoma tissues and cell lines was detected using reverse transcription‑quantitative PCR (RT‑qPCR) and western blotting. The effects of KRT17 on osteosarcoma cell proliferation and the Warburg effect in vitro were detected using CCK‑8 and colony formation assays, cell cycle distribution analysis and metabolic measures. The effects of KRT17 on osteosarcoma cell proliferation in vivo were detected using a subcutaneous tumorigenesis model. The association between KRT17 and the AKT/mTOR/hypoxia‑inducible factor 1α (HIF1α) pathway was detected using RT‑qPCR and western blotting. The results demonstrated that KRT17 was highly expressed in osteosarcoma tissues and cell lines. Knockdown of KRT17 decreased osteosarcoma cell proliferation and colony formation, induced G1 phase arrest and inhibited glycolysis in vitro. Similarly, the suppression of KRT17 decreased osteosarcoma tumor growth in vivo. Knockdown of KRT17 decreased the expression of phosphorylated (p)‑AKT, p‑mTOR, HIF1α and the target gene of HIF1α glucose transporter 1. Restoring the expression of p‑AKT, p‑mTOR or HIF1α reversed the effect of KRT17 inhibition on cell proliferation and glycolysis. These results indicated that knockdown of KRT17 may be an effective method for treating osteosarcoma through inhibiting osteosarcoma cell proliferation and the Warburg effect by suppressing the AKT/mTOR/HIF1α pathway.

Propranolol inhibits proliferation and induces apoptosis of hemangioma-derived endothelial cells via Akt pathway by down-regulating Ang-2 expression

Hemangioma is one of the commonest benign vascular tumors among children. Propranolol is the first-line therapeutic drug for hemangioma. However, the effects and mechanisms of propranolol in hemangioma have not been thoroughly elaborated. In this study, the effects and mechanisms of propranolol were explored using hemangioma-derived endothelial cells (HemECs). The expression of GLUT1 were determined by immunofluorescence staining. qRT-PCR assay was conducted to detect the mRNA expressions of angiopoietin-2 (Ang-2) and Tie-2. Western blot assay was carried out to measure the protein levels of Ang-2, Tie-2, protein kinase-B (Akt) and phospholyrated-Akt (p-Akt). Cell proliferation was assessed by Cell Counting Kit-8 (CCK-8) assay and Western blot of Ki67 protein level. Cell apoptosis was measured by flow cytometry analysis and Western blot of Bax and Bcl-2 levels. We found that propranolol inhibited proliferation and induced apoptosis in human umbilical vein endothelial cells (HUVECs) and HemECs. Moreover, propranolol inhibited the expressions of Ang-2 and Tie-2 in HUVECs and HemECs. Functional analysis revealed that Ang-2 attenuated the effects of propranolol on HemEC proliferation and apoptosis. Mechanistical analysis showed that propranolol inhibited the Akt pathway by regulating Ang-2 expression in HemECs. Futhermore, inhibition of the Akt pathway attenuated the effects of Ang-2 on proliferation and apoptosis in HemECs. In conclusion, propranolol inhibited proliferation and induced apoptosis of HemECs via Akt pathway by down-regulating Ang-2 expression, which contributes to our understanding on the pathogenesis of hemangioma and promotes the development of therapeutic approaches for hemangioma.

Progress in the treatment of infantile hemangioma

Infantile hemangioma (IH) is a common benign tumor, which mostly resolves spontaneously; however, children with high-risk IH need treatment. Currently, the recognized first-line treatment regimen for IH is oral propranolol, but research on the pathogenesis of IH has led to the identification of new therapeutic targets, which have shown good curative effects, providing more options for disease treatment. This article summarizes the applications of different medications, dosages, and routes of administration for the treatment of IH. In addition to drug therapy, this article also reviews current therapeutic options for IH such as laser therapy, surgical treatment, and observation. To provide the best treatment, therapeutic regimens for IH should be selected based on the child's age, the size and location of the lesion, the presence of complications, the implementation conditions, and the potential outcomes of the treatment.

Lauryl Gallate Induces Apoptotic Cell Death through Caspase-dependent Pathway in U87 Human Glioblastoma Cells In Vitro

BACKGROUND/AIM

The treatment of human glioma tumor is still an unmet medical need. Natural products are always promising resources for discovery of anticancer drugs. Lauryl gallate (LG) is one of the derivatives of gallic acid, widely present in plants, that has been shown to induce anticancer activities in many human cancer cell lines; however, it has not been studied in human glioma cell lines. Thus, the effects of LG on human glioblastoma U87 cells were investigated in the present in vitro study.

MATERIALS AND METHODS

Cell morphology and viability were examined by phase-contrast microscopy. Annexin V/Propidium iodide (PI) double staining were performed and assayed by flow cytometry to confirm that viable cell number reduction was due to the induction of apoptosis. Furthermore, U87 cells were exposed to LG in various concentrations and were analyzed by caspase activity assay. To further confirm that LG induced apoptotic cell death, the expression of apoptosis-associated proteins in LG-treated U87 cells was tested by western blot.

RESULTS

LG induced morphological changes and decreased viability in U87 cells. Annexin V/PI double staining revealed that LG induced apoptotic cell death in U87 cells in a dose-dependent manner. The increased activities of caspase-2, -3, -8 and -9 demonstrated that LG induced U87 cell apoptosis through a caspase-dependent pathway. In terms of molecular level, LG increased pro-apoptotic proteins Bax and Bak and decreased anti-apoptotic protein Bcl-2 in U87 cells. Furthermore, LG also suppressed the expression of p-Akt, Pak1, Hif-1α and Hif-2α, β-catenin and Tcf-1 in U87 cells.

CONCLUSION

These results suggest that LG induced apoptotic cell death via the caspase-dependent pathway in U87 cells.

Effects of curcumin on hypoxia-inducible factor as a new therapeutic target

Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that consists of two subunits, the HIF-1α and HIF-1β (ARNT). Under hypoxic conditions, HIF-1 is an adaptive system that regulates the transcription of multiple genes associated with growth, angiogenesis, proliferation, glucose transport, metabolism, pH regulation and cell death. However, aberrant HIF-1 activation contributes to the pathophysiology of several human diseases such as cancer, ischemic cardiovascular disorders, and pulmonary and kidney diseases. A growing body of evidence indicates that curcumin, a natural bioactive compound of turmeric root, significantly targets both HIF-1 subunits, but is more potent against HIF-1α. In this review, we have summarized the knowledge about the pharmacological effects of curcumin on HIF-1 and the related molecular mechanisms that may be effective candidates for the development of multi-targeted therapy for several human diseases.