The caspase 3-dependent apoptotic effect of pycnogenol in human oral squamous cell carcinoma HSC-3 cells

Role of Phytoconstituents in Cancer Treatment: A Review

Over the years, natural compounds have become a significant advancement in cancer treatment, primarily due to their effectiveness, safety, bio-functionality, and wide range of molecular structures. They are now increasingly preferred in drug discovery due to these attributes. These compounds, whether occurring naturally or with synthetic modifications, find applications in various fields like biology, medicine, and engineering. While chemotherapy has been a successful method for treating cancer, it comes with systemic toxicity. To address this issue, researchers and medical practitioners are exploring the concept of combinational chemotherapy. This approach aims to reduce toxicity by using a mix of natural substances and their derivatives in clinical trials and prescription medications. Among the most extensively studied natural anticancer compounds are quercetin, curcumin, vincristine, and vinblastine. These compounds play crucial roles as immunotherapeutics and chemosensitizers, both as standalone treatments and in combination therapies with specific mechanisms. This review article provides a concise overview of the functions, potentials, and combinations of natural anticancer compounds in cancer treatment, along with their mechanisms of action and clinical applications.

The Role of Zinc in Bone Tissue Health and Regeneration-a Review

Zinc is a micronutrient of key importance for human health. An increasing number of studies indicate that zinc plays a significant role in bone tissue's normal development and maintaining homeostasis. Zinc is not only a component of bone tissue but is also involved in the synthesis of the collagen matrix, mineralization, and bone turnover. It has been demonstrated that zinc can stimulate runt-related transcription factor 2 (Runx2) and promote the differentiation of osteoblasts. On the other hand, zinc has been found to inhibit osteoclast-like cell formation and to decrease bone resorption by stimulating osteoclasts' apoptosis. Moreover, zinc regulates the RANKL/RANK/OPG pathway, thereby facilitating bone remodeling. To date, not all mechanisms of Zn activity on bone tissue are well understood and documented. The review aimed to present the current state of research on the role of zinc in bone tissue, its beneficial properties, and its effects on bone regeneration. Since calcium phosphates as bone substitute materials are increasingly enriched in zinc ions, the paper included an overview of research on the potential role of such materials in bone filling and regeneration.

Bone marrow mesenchymal stem cellsderived exosomes stabilize atherosclerosis through inhibiting pyroptosis

OBJECTIVES

This study aimed to determine the effects of bone marrow mesenchymal stem cells (BMSCs)-derived exosomes (BMSC-EXO) on atherosclerosis (AS), and its related underlying mechanisms.

METHODS

Exosomes were isolated from mouse BMSCs, and identified by transmission electron microscopy (TEM), Nanosight (NTA), and western blot. A mouse AS model was established, and exosomes were injected into the tail vein. Total cholesterol (TC) and triglycerides (TG) were detected using their corresponding assay kits. The contents of IL-1β and IL-18 in serum were detected by ELISA. The mRNA and protein expression levels of GSDMD, Caspase1, and NLRP3 were detected by qRT-PCR and Western blot. Finally, aortic tissues in the Model and BMSC-EXO groups were sent for sequencing.

RESULTS

TEM, NTA, and western blot indicated successful isolation of exosomes. Compared with the control group, the TC, TG contents, IL-1β and IL-18 concentrations of the mice in the Model group were significantly increased; nonetheless, were significantly lower after injected with BMSC-EXO than those in the Model group (p < 0.05). Compared with the control group, the expressions of NLRP3, caspase-1 and GSDMD were significantly up-regulated in the Model group (p < 0.05), while the expressions of NLRP3, caspase-1, and GSDMD were significantly down-regulated by BMSC-EXO. By sequencing, a total of 3852 DEGs were identified between the Model and BMSC-EXO group and were significantly enriched in various biological processes and pathways related to mitochondrial function, metabolism, inflammation, and immune response.

CONCLUSION

AS can induce pyroptosis, and BMSC-EXO can reduce inflammation and alleviate the progression of AS by inhibiting NLRP3/Caspase-1/GSDMD in the pyroptosis pathway.

Natural Products as Anticancer Agents: Current Status and Future Perspectives

Natural products have been an invaluable and useful source of anticancer agents over the years. Several compounds have been synthesized from natural products by modifying their structures or by using naturally occurring compounds as building blocks in the synthesis of these compounds for various purposes in different fields, such as biology, medicine, and engineering. Multiple modern and costly treatments have been applied to combat cancer and limit its lethality, but the results are not significantly refreshing. Natural products, which are a significant source of new therapeutic drugs, are currently being investigated as potential cytotoxic agents and have shown a positive trend in preclinical research and have prompted numerous innovative strategies in order to combat cancer and expedite the clinical research. Natural products are becoming increasingly important for drug discovery due to their high molecular diversity and novel biofunctionality. Furthermore, natural products can provide superior efficacy and safety due to their unique molecular properties. The objective of the current review is to provide an overview of the emergence of natural products for the treatment and prevention of cancer, such as chemosensitizers, immunotherapeutics, combinatorial therapies with other anticancer drugs, novel formulations of natural products, and the molecular mechanisms underlying their anticancer properties.

Induction of Human Oral Squamous Carcinoma Apoptosis by Derris scandens Benth and Elephantopus scaber Linn Extracts

D scandens ( Derris scandens Benth.) and E scaber ( Elephantopus scaber Linn.) contain flavonoids and phenolic acids, which have antitumor activity in various cancer cell lines. Oral cancer is among the most common cancers in Southeast Asia, and the survival rate remains low. Thus, this study screened 2 ethanolic plant extracts for cytotoxicity on the oral human squamous carcinoma cell line (HSC-2), and compared the mechanisms of action. Extracts of D scandens and E scaber showed cytotoxicity against HSC-2 cells in a dose-dependent manner. Observation of nuclear morphology by Hoechst 33342 staining revealed chromatin condensation. Apoptosis was confirmed by Annexin V-FITC staining and cell sorting (fluorescence-activated cell sorting) analysis. We demonstrated that cancer apoptosis was accompanied by changes in the expression of procaspase 3 and that D scandens-mediated apoptosis in HSC-2 cells was potentiated by protein kinase B (Akt) and B-cell lymphoma-2 (Bcl-2), while E scaber apoptosis was mediated by mitogen-activated protein kinase (MAPK) pathways, involving stress-activated protein kinases/jun amino-terminal kinase (SAPK/JNK) and p38-MAPK. Further investigation into targets for apoptosis induction by these plant extracts may have potential in oral cancer therapy.

Protective Effect of Pycnogenol against Methotrexate-Induced Hepatic, Renal, and Cardiac Toxicity: An In Vivo Study

Methotrexate (MTX) is one of the most commonly used chemotherapies for various types of cancer, including leukemia, breast cancer, hepatocarcinoma, and gastric cancers. However, the efficacy of MTX is frequently limited by serious side effects. Several studies have reported that the cytotoxic effect of MTX is not limited to cancer cells but can also affect normal tissues, leading to prospective damage to many organs. In the present study, we extensively investigated the molecular and microscopic basis of MTX-induced toxicity in different organs (liver, kidney, and heart) and explored the possible protective effect of pycnogenol, a polyphenolic component extracted from the bark of P. pinaster, to attenuate these effects. Biochemical analysis revealed that administration of MTX significantly reduced the function of the liver, kidney, and heart. Histological and immunohistochemical analysis indicated that MTX treatment caused damage to tissues of different organs. Interestingly, administration of pycnogenol (10, 20, and 30 mg/kg) significantly attenuated the deterioration effects of MTX on different organs in a dose-dependent manner, as demonstrated by biochemical and histological analysis. Our results reveal that pycnogenol successfully ameliorated oxidative damage and reduced toxicity, inflammatory response, and histological markers induced by methotrexate treatment. Taken together, this study provides solid evidence for the pharmacological application of pycnogenol to attenuate damage to different organs induced by MTX treatment.

An In Vitro Study on the Interactions of Pycnogenol® with Cisplatin in Human Cervical Cancer Cells

Objectives

In the treatment of cancer, it is intended to increase the anticancer effect and decrease cytotoxicity using various plant-derived phenolic compounds with chemotherapeutic drugs. Pycnogenol^® (PYC), a phenolic compound, has been the subject of many studies. Since the mechanisms of the interactions of PYC with cisplatin need to be clarified, we aimed to determine the effects of PYC on cisplatin cytotoxicity in human cervix cancer cells (HeLa) and to evaluate the genotoxicity of PYC.

Materials and Methods

The cytotoxicity of cisplatin and PYC was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in HeLa cells for 24 h and 48 h. The effect of PYC against oxidative DNA damage was evaluated using the comet assay.

Results

The IC₅₀ values of cisplatin were 22.4 μM and 12.3 μM for 24 h and 48 h, respectively. The IC₅₀ values of PYC were 261 μM and 213 μM for 24 h and 48 h, respectively. For 24 h exposure, PYC significantly reduced the IC₅₀ value of cisplatin at the selected concentrations (15.6-500 μM). For 48 h exposure, PYC did not change the cytotoxicity of cisplatin at concentrations between 15.6 and 125 μM, but significantly reduced it at concentrations of 250 μM and 500 μM. PYC alone did not induce DNA damage at concentrations of 10 μM or 25 μM; however, it significantly induced DNA damage at higher concentrations (50-100 μM). It also significantly reduced H₂O₂-induced DNA damage at all concentrations studied (10-100 μM).

Conclusion

Our results suggest that PYC may increase the cisplatin cytotoxicity in HeLa cells at nongenotoxic doses. The results might contribute to the anticancer effect of cisplatin with PYC in cervical carcinoma, but in order to confirm this result further in vitro studies with cancer cell lines and in vivo studies are needed.

Apoptosis induced by methanol extract of Potentilla discolor in human mucoepidermoid carcinoma cells through STAT3/PUMA signaling axis

Potentilla discolor has been used in traditional Chinese medicine for the treatment of hyperglycemia. However, the potential role of Potentilla discolor against cancer and its mode of action remain to be fully elucidated. The present study explored the apoptotic effect of methanol extract of Potentilla discolor (MEPD) in human mucoepidermoid carcinoma (MEC) cell lines of salivary glands. MEPD markedly suppressed the growth and induced apoptotic cell death in MC3 and YD15 cells. MEPD treatment significantly upregulated the expression of PUMA and reduced STAT3 phosphorylation. Overexpression of STAT3 partially recovered the growth of MEC cells inhibited by MEPD. In addition, dephosphorylation of STAT3 by cryptotanshinone (a potent STAT3 inhibitor) was sufficient to inhibit the growth of MEC cells and induce apoptosis via affecting PUMA protein. These results suggest that MEPD has a potential anticancer property via the STAT3/PUMA signaling axis in human MEC cells of salivary gland.

Pycnogenol Cytotoxicity in Pancreatic INS-1E β cells Induced by Calcium Dysregulation

Natural standardized flavonoid extract from the bark of Pinus pinaster, Pycnogenol (Pyc), was recently found to decrease intensively the activity of sarcoplasmic reticulum Ca²⁺ -ATPase of rabbit skeletal muscle (SERCA1). On the basis of this inhibitory effect in a cell-free system and similarities of SERCA1 to its other isoforms, proapoptotic properties of Pyc may be expected in cellular systems. Pycnogenol (40-100 μg/mL) induced a concentration-dependent decrease of the viability of pancreatic INS-1E β cells associated with induction of apoptosis. In addition, intracellular Ca²⁺ level increase was found along with reduction of protein expression level of SERCA2b and impairment of insulin secretion by β cells. These facts indicate that Pyc may induce apoptosis by impairment of calcium homeostasis. Copyright © 2017 John Wiley & Sons, Ltd.

Tanshinone IIA sensitizes oral squamous cell carcinoma to radiation due to an enhanced autophagy

PURPOSE

Tanshinone IIA (TanIIA), which is derived from the roots of Salvia miltiorrhiza (Danshen), has multiple pharmacological activities. However, the radiosensitivezing activity of TanIIA in oral cancer cells has not been studied extensively. The purpose of this study is to investigate the radiosensitizing effects of TanIIA in human oral squamous cell carcinoma SCC090 and examined the underlying mechanisms.

METHODS

Clonogenic assay was used to investigate the radiosensitizing effect of TanIIA on SCC090. And then, apoptosis and reactive oxygen species (ROS) induced by the combination of TanIIA with radiation were analyzed by Flow cytometry. Finally, autophagy was detected by monodansylcadervarine (MDC) staining.

RESULTS

TanIIA could significantly sensitize SCC090 to radiation. Meanwhile, an increase ROS generation after exposed to the combination treatment was found. In addition, the protein levels of Beclin 1, Atg5 and LC3-II, three important proteins involved in autophagy were increased in cells.

CONCLUSIONS

TanIIA exerted a strong radiosensitizing effect on SCC090 comparing with the simple drug or single radiation treatment, which was due to an enhanced ROS generation and autophagy.

Does Notch play a tumor suppressor role across diverse squamous cell carcinomas?

The role of Notch pathway in tumorigenesis is highly variable. It can be tumor suppressive or pro‐oncogenic, typically depending on the cellular context. Squamous cell carcinoma (SCC) is a cancer of the squamous cell, which can occur in diverse human tissues. SCCs are one of the most frequent human malignancies for which the pathologic mechanisms remain elusive. Recent genomic analysis of diverse SCCs identified marked levels of mutations in NOTCH1, implicating Notch signaling pathways in the pathogenesis of SCCs. In this review, evidences highlighting NOTCH's role in different types of SCCs are summarized. Moreover, based on accumulating structural information of the NOTCH receptor, the functional consequences of NOTCH1 gene mutations identified from diverse SCCs are analyzed, emphasizing loss of function of Notch in these cancers. Finally, we discuss the convergent view on an intriguing possibility that Notch may function as tumor suppressor in SCCs across different tissues. These mechanistic insights into Notch signaling pathways will help to guide the research of SCCs and development of therapeutic strategies for these cancers.