Combination treatment of ligustrazine piperazine derivate DLJ14 and adriamycin inhibits progression of resistant breast cancer through inhibition of the EGFR/PI3K/Akt survival pathway and induction of apoptosis

The medicinal chemistry of piperazines: A review

The versatile basic structure of piperazine allows for the development and production of newer bioactive molecules that can be used to treat a wide range of diseases. Piperazine derivatives are unique and can easily be modified for the desired pharmacological activity. The two opposing nitrogen atoms in a six-membered piperazine ring offer a large polar surface area, relative structural rigidity, and more acceptors and donors of hydrogen bonds. These properties frequently result in greater water solubility, oral bioavailability, and ADME characteristics, as well as improved target affinity and specificity. Various synthetic protocols have been reported for piperazine and its derivatives. In this review, we focused on recently published synthetic protocols for the synthesis of the piperazine and its derivatives. The structure-activity relationship concerning different biological activities of various piperazine-containing drugs has also been highlighted to provide a good understanding to researchers for future research on piperazines.

Can Natural Products Targeting EMT Serve as the Future Anticancer Therapeutics?

Cancer is the leading cause of death and has remained a big challenge for the scientific community. Because of the growing concerns, new therapeutic regimens are highly demanded to decrease the global burden. Despite advancements in chemotherapy, drug resistance is still a major hurdle to successful treatment. The primary challenge should be identifying and developing appropriate therapeutics for cancer patients to improve their survival. Multiple pathways are dysregulated in cancers, including disturbance in cellular metabolism, cell cycle, apoptosis, or epigenetic alterations. Over the last two decades, natural products have been a major research interest due to their therapeutic potential in various ailments. Natural compounds seem to be an alternative option for cancer management. Natural substances derived from plants and marine sources have been shown to have anti-cancer activity in preclinical settings. They might be proved as a sword to kill cancerous cells. The present review attempted to consolidate the available information on natural compounds derived from plants and marine sources and their anti-cancer potential underlying EMT mechanisms.

Tetramethylpyrazine: A Review of Its Antitumor Potential and Mechanisms

Cancer remains a major public health threat. The mitigation of the associated morbidity and mortality remains a major research focus. From a molecular biological perspective, cancer is defined as uncontrolled cell division and abnormal cell growth caused by various gene mutations. Therefore, there remains an urgent need to develop safe and effective antitumor drugs. The antitumor effect of plant extracts, which are characterized by relatively low toxicity and adverse effect, has attracted significant attention. For example, increasing attention has been paid to the antitumor effects of tetramethylpyrazine (TMP), the active component of the Chinese medicine Chuanqiong, which can affect tumor cell proliferation, apoptosis, invasion, metastasis, and angiogenesis, as well as reverse chemotherapeutic resistance in neoplasms, thereby triggering antitumor effects. Moreover, TMP can be used in combination with chemotherapeutic agents to enhance their effects and reduce the side effect associated with chemotherapy. Herein, we review the antitumor effects of TMP to provide a theoretical basis and foundation for the further exploration of its underlying antitumor mechanisms and promoting its clinical application.

Hydrazine-Containing Heterocycle Cytochalasan Derivatives From Hydrazinolysis of Extracts of a Desert Soil-Derived Fungus Chaetomium madrasense 375

"Diversity-enhanced extracts" is an effective method of producing chemical libraries for the purpose of drug discovery. Three rare new cytochalasan derivative chaetoglobosins B1-B3 (1-3) were obtained from chemically engineered crude broth extracts of Chaetomium madrasense 375 prepared by reacting with hydrazine monohydrate and four known metabolite chaetoglobosins (4-7) were also identified from the fungus. The structures were identified by NMR and MS analysis and electronic circular dichroism simulation. In addition, the antiproliferative activities of these compounds were also evaluated, and the drug-resistant activities of cytochalasans were evaluated for the first time. Compound 6 possessed potent activity against four human cancer cells (A549, HCC827, SW620, and MDA-MB-231), and two drug-resistant HCC827 cells (Gefitinib-resistant, Osimertinib-resistant) compared with the positive controls.

Ligustrazine inhibits the proliferation and migration of ovarian cancer cells via regulating miR-211

Ovarian cancer (OC) is a commonly diagnosed female cancer. Ligustrazine (LSZ), a natural compound, has been reported to exert anti-cancer activity, although the mechanisms underlying the anti-cancer effects are not clear. The present study investigated the impact of LSZ on cell proliferation and migration by regulating microRNA-211 (miR-211) expression using the human ovarian cancer SK-OV-3 and OVCAR-3 cell lines. OC cells were treated with 0, 0.5, 1, and 2 mM LSZ, and quantitative real-time PCR was utilized to measure miR-211 levels in SK-OV-3 and OVCAR-3 cells with different treatment. Moreover, to further confirm the roles of miR-211 in LSZ induced anti-tumor effects, miR-211 expression was inhibited by transfection of miR-211 inhibitors in SK-OV-3 cells. Cell proliferation of transfected cells was evaluated using the CCK-8 and colony formation assay. The scratch assay was employed to assess cell migration and transwell assay was performed for evaluating the cell invasion. Protein levels of epithelial-mesenchymal transition (EMT) markers were determined by Western blotting. We found that LSZ inhibited the viability, proliferation, migration and invasion ability of SK-OV-3 and OVCAR-3 cells in a dose-dependent manner; moreover, LSZ could significantly increase the expression of miR-211 in both SK-OV-3 and OVCAR-3, and knockdown of miR-211 in SK-OV-3 cells partially abrogated the anti-tumor behavior of LSZ by promoting the viability, proliferation, migration, invasion and EMT of SK-OV-3 cells. Thus, we found that LSZ can inhibit the proliferation and migration of OC cells via regulating miR-211. Our study suggests that LSZ might be a potential and effective treatment for OC.

DpdtbA-Induced Growth Inhibition in Human Esophageal Cancer Cells Involved Inactivation of the p53/EGFR/AKT Pathway

Esophageal cancer (ESC) is one of the most deadly diseases for human. p53 in most cancers, including ESC cell, is mutated, and the mutated p53 losses its original function and acquires “gain of function” that allows for promoting the hallmarks of cancer, such as antiapoptosis, metastasis, invasion, angiogenesis, and resistance to chemotherapy. Targeting p53 through either introducing wild-type or degrading mutated p53 is an important strategy in cancer therapy. Di-2,2′-pyridine ketone dithiocarbamate s-butyric acid (DpdtbA) has significant growth inhibition against gastric cancer lines in previous study. Similar action in ESC cell lines but a novel molecular mechanism was observed in the present study. The results showed that DpdtbA exhibited an excellent antiproliferative effect for ESC cell lines (IC₅₀ ≤ 4.5 ± 0.4 μM for Kyse 450, 3.2 ± 0.6 μM for Kyse 510 cell, and 10.0 ± 0.6 μM for Kyse 150) and led to cell cycle arrest at the S phase which correlated to CDK2 downregulation. The mechanistic study suggested that growth inhibition was related to ROS-mediated apoptosis, and ROS production was due to SOD inhibition initiated by DpdtbA rather than occurrence of ferritinophagy. In addition, DpdtbA also induced a downregulation of EGFR, p53, and AKT, which hinted that mutant p53 still played a role in the regulation of its downstream targets. Further study revealed that the downregulation of p53 was through stub1- (chip-) mediated autophagic degradation rather than MDM2-mediated ubiquitination. Taken together, the DpdtbA-induced growth inhibition in a mechanism was through inactivating the p53/EGFR/AKT signal pathway.

Study on preparation, characterization and multidrug resistance reversal of red blood cell membrane-camouflaged tetrandrine-loaded PLGA nanoparticles

The multidrug resistance in tumor (MDR) is a major barrier to efficient cancer therapy. Modern pharmacological studies have proven that tetrandrine (TET) has great potential in reversing MDR. However, it has a series of medication problems in clinic such as poor water solubility, low oral bioavailability and short half-life in vivo. Aiming at the above problems, red blood cell membrane-camouflaged TET-loaded poly(lactic-co-glycolic acid) (PLGA) nanoparticles (RPTNs) had been developed. The RPTNs had spherical shell-core double layer structure with average particle size of 164.1 ± 1.65 nm and encapsulation efficiency of 84.1% ± 0.41%. Compared with TET-PLGA nanoparticles (PTNs), the RPTNs reduced RAW 264.7 macrophages’ swallowing by 32% due to its retention of natural membrane proteins. The cumulative drug release of RPTNs was 81.88% within 120 h. And pharmacokinetic study showed that the blood half-life of RPTNs was 19.38 h, which was 2.95 times of free drug. When RPTNs of 2 μg/mL TET were administered in combination with adriamycin (ADR), significant MDR reversal effect was observed in drug-resistant cells MCF-7/ADR. In a word, the RPTNs hold potential to improve its efficacy and broaden its clinical application.

Recent progress in the structural modification and pharmacological activities of ligustrazine derivatives

Ligustrazine is a main active fraction of the traditional medicine known as Ligusticum chuanxiong hort, which has been used as clinical medication for cerebral thrombosis, coronary heart disease and stenocardia recently. The rapid metabolism and short half-life of ligustrazine seriously limits its application in clinical practice. Therefore, derivatives of ligustrazine are designed and synthesized in our and other labs, including piperazine, cinnamic acid, styrene, acylguanidine, amides, curcumin and triterpenes derivatives of ligustrazine. Most of these compounds present better pharmacodynamics activities and more favorable pharmacokinetic properties compared to the parent compound. Besides, some new biological activities of these compounds are discovered. Hence, this review continues the previous review of our group as well as aims to highlight recent prominent advances in this field in the past ten years.

Tetramethylpyrazine regulates breast cancer cell viability, migration, invasion and apoptosis by affecting the activity of Akt and caspase-3

Tetramethylpyrazine (TMP), an effective component of the traditional Chinese medicine Chuanxiong Hort, has been proven to exhibit a beneficial effect in a number of types of malignant epithelial cancer. However, the mode of action of TMP on breast cancer cells remains unknown. The aim of the present study was to investigate the regulatory effect of TMP on breast cancer cells and its underlying molecular mechanism of action. Different concentrations of TMP were used to treat breast cancer cells, and subsequently, the effects on the viability, apoptosis, and migration and invasion abilities were determined. In addition, the expression and activity levels of the protein kinase B (Akt) signaling pathway and caspase-3 were explored via reverse transcription-quantitative polymerase chain reaction and western blot analysis. The results of the present study revealed that TMP significantly inhibited the viability, migration and invasion rates, and increased the apoptosis of MDA-MB-231 cells in a dose-dependent manner. The minimum effective dose was ~1,600 µM. Additional mechanistic studies demonstrated that 1,600 and 3,200 µM TMP significantly decreased the gene expression and activity of Akt and increased the activity of caspase-3. This mechanism may be responsible for the inhibition of viability, migration and invasion, and activation of apoptosis in breast cancer cells. The results of the present study suggested that TMP may be used in chemotherapy against breast cancer.

Efficacy of melatonin, IL-25 and siIL-17B in tumorigenesis-associated properties of breast cancer cell lines

Mammary tumorigenesis can be modulated by melatonin, which has oncostatic action mediated by multiple mechanisms, including the inhibition of the activity of transcription factors such as NF-κB and modulation of interleukins (ILs) expression. IL-25 is an active cytokine that induces apoptosis in tumor cells due to differential expression of its receptor (IL-17RB). IL-17B competes with IL-25 for binding to IL-17RB in tumor cells, promoting tumorigenesis. This study purpose is to address the possibility of engaging IL-25/IL-17RB signaling to enhance the effect of melatonin on breast cancer cells. Breast cancer cell lines were cultured monolayers and 3D structures and treated with melatonin, IL-25, siIL-17B, each alone or in combination. Cell viability, gene and protein expression of caspase-3, cleaved caspase-3 and VEGF-A were performed by qPCR and immunofluorescence. In addition, an apoptosis membrane array was performed in metastatic cells. Treatments with melatonin and IL-25 significantly reduced tumor cells viability at 1mM and 1ng/mL, respectively, but did not alter cell viability of a non-tumorigenic epithelial cell line (MCF-10A). All treatments, alone and combined, significantly increased cleaved caspase-3 in tumor cells grown as monolayers and 3D structures (p<0.05). Semi-quantitative analysis of apoptosis pathway proteins showed an increase of CYTO-C, DR6, IGFBP-3, IGFBP-5, IGFPB-6, IGF-1, IGF-1R, Livin, P21, P53, TNFRII, XIAP and hTRA proteins and reduction of caspase-3 (p<0.05) after melatonin treatment. All treatments reduced VEGF-A protein expression in tumor cells (p<0.05). Our results suggest therapeutic potential, with oncostatic effectiveness, pro-apoptotic and anti-angiogenic properties for melatonin and IL-25-driven signaling in breast cancer cells.

Synthesis of folate‑chitosan nanoparticles loaded with ligustrazine to target folate receptor positive cancer cells

In addition to its vasodilatory effect, ligustrazine (LZ) improves the sensitivity of multidrug resistant cancer cells to chemotherapeutic agents. To enhance the specificity of LZ delivery to tumor cells/tissues, folate-chitosan nanoparticles (FA-CS-NPs) were synthesized by combination of folate ester with the amine group on chitosan to serve as a delivery vehicle for LZ (FA-CS-LZ-NPs). The structure of folate-chitosan and characteristics of FA-CS-LZ-NPs, including its size, encapsulation efficiency, loading capacity and release rates were analyzed. MCF-7 (folate receptor-positive) and A549 (folate receptor-negative) cells cultured with or without folate were treated with FA-CS-LZ-NPs, CS-LZ-NPs or LZ to determine cancer-targeting specificity of FA-CS-LZ-NPs. Fluorescence intensity of intracellular LZ was observed by laser scanning confocal microscopy, and concentration of intracellular LZ was detected by HPLC. The average size of FA-CS-LZ-NPs was 182.7±0.56 nm, and the encapsulation efficiency and loading capacity was 59.6±0.23 and 15.3±0.16% respectively. The cumulative release rate was about 95% at pH 5.0, which was higher than that at pH 7.4. There was higher intracellular LZ accumulation in MCF-7 than that in A549 cells and intracellular LZ concentration was not high when MCF-7 cells were cultured with folate. These results indicated that the targeting specificity of FA-CS-LZ-NPs was mediated by folate receptor. Therefore, the FA-CS-LZ-NPs may be a potential folate receptor-positive tumor cell targeting drug delivery system that could possibly overcome multidrug resistance during cancer therapy.

Increased MIR31HG lncRNA expression increases gefitinib resistance in non-small cell lung cancer cell lines through the EGFR/PI3K/AKT signaling pathway

The aim of the present study was to gain insight into the molecular mechanism of gefitinib resistance in non-small cell lung cancer (NSCLC), and demonstrate whether long noncoding RNA (lncRNA) expression signatures differ between gefitinib-sensitive PC9 and gefitinib-resistant PC9 (PC9-R) cell lines. PC9 and PC9-R cells were treated with gefitinib and, after 48 h, proliferation and apoptosis were analyzed using a Cell Counting Kit-8 (CCK-8) assay and flow cytometry. Microarray expression profiling of lncRNAs was undertaken in both PC9 and PC9-R cells, and the expression profiles were verified by reverse transcription quantitative-polymerase chain reaction. The EGFR/PI3K/AKT signaling pathway and mitochondrial apoptosis protein expression levels were assessed by western blot analysis. The PC9 cell line treated with gefitinib had a more significant effect on cell viability and apoptosis than the PC9-R cell line (P<0.05). Expression of various lncRNAs differed significantly between the two cell lines, and MIR31HG expression in particular was significantly higher in PC9-R cells. As expected, MIR31HG lncRNA knockdown sensitized PC9-R cells to gefitinib, and further experiments revealed that turning off the EGFR/PI3K/AKT signaling pathway activated expression of p53 in PC9-R cells transfected with si-MIR31HG. Furthermore, PC9-R cells transfected with si-MIR31HG induced cell apoptosis through the mitochondrial apoptosis pathway, and arrested the cell cycle in the G0/G1 phase. The results of the current study suggest that MIR31HG lncRNA levels in PC9-R cells are higher than in PC9 cells. Furthermore, overexpression of MIR31HG lncRNAs may contribute to gefitinib resistance in PC9-R cells through the EGFR/PI3K/AKT pathway, which impacts on cell proliferation, apoptosis and the cell cycle. MIR31HG lncRNA may therefore be a novel candidate biomarker for future therapeutic strategies involving EGFR-TKIs.

Alantolactone exhibited anti-herpes simplex virus 1 (HSV-1) action in vitro

The aim of this study was to determine the inhibitory action of alantolactone, a gradient of traditional Chinese medicine Inulae Radix (Tu-Mu-Xiang), on herpes simplex virus 1 (HSV-1). African green monkey kidney cells (Vero cells) were infected with HSV-1 and the protective effects of alantolactone on Vero cells were examined. At concentrations of 10(-6), 10(-7), and 10(-8) g/mL, alantolactone did not have a marked harmful effect on the viability of Vero cells according to an MTT assay. Based on the cytopathic effect (CPE) and MTT assays, alantolactone at these concentrations exhibited antiviral action and protected cells from being damaged by HSV-1. Results indicated that alantolactone had potent anti-HSV-1 action and provided evidence for use of Inulae Radix in the treatment of HSV-1 infection.

Therapeutic Effect of External Application of Ligustrazine Combined with Holistic Nursing on Pressure Sores

Background

This study aimed to explore the therapeutic effect of external application of ligustrazine combined with holistic nursing on pressure sores, as well as the underlying mechanism.

Material/Methods

From February 2014 to March 2015, a total of 32 patients with Phase II and Phase III pressure sores were enrolled and randomly assigned to an experimental group or a control group. The clinical data were comparable between the 2 groups. In addition to holistic nursing, the patients in the experimental group received 4 weeks of continuous external application of ligustrazine, whereas patients in the control group received compound clotrimazole cream. Therapeutic effect and healing time were recorded. HaCaT cells were used as an in vitro model for mechanism analysis of the effect of ligustrazine in treating pressure sores. After culturing with different concentrations of ligustrazine or the inhibitor of AKT (LY294002) for 72 h, cell viability, clone formation numbers, and levels of phosphatidyl inositol 3-kinase (PI3K), p-AKT, and p-mammalian target of rapamycin (mTOR) were determined.

Results

Compared to the control group, the total effective rate in the experimental group was significantly higher, and the healing time was significantly reduced. Cell viability and clone formation numbers were significantly upregulated by ligustrazine in a dose-dependent manner. Both the cell viability and clone formation numbers were significantly inhibited by application of LY294002.

Conclusions

Our results suggest that ligustrazine combined with holistic nursing is an effective treatment of pressure sores. The protective effect may be associated with the promotion of cell growth by activation of the PI3K/AKT pathway.

A Case of Recurrent Hepatocellular Carcinoma Acquiring Complete Remission of Target Lesion With Treatment With Traditional Chinese Medicine

Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies worldwide. Although surgery is known as the most promising radical treatment, a high recurrent or metastatic rate after surgery has limited its clinical efficacy. Sorafenib, a target agent, has seemed to be the only option for metastatic HCC patients to date, but none of clinical trials showed it could prolong the overall survival (OS) of advanced HCC to 1 year. How to prolong the OS and improve cure rate of HCC patients is still beset with difficulties. This report presents a rare case of recurrent HCC patient with complete regression of target lesion with 2 years of Chinese herbal treatment. A 64-year-old Chinese man with hepatitis B virus–associated chronic hepatitis presented HCC has been clinically diagnosed tumor relapse and omentum metastasis with computed tomography and α-fetoprotein blood test 4 months after surgery. It was decided the patient would receive traditional Chinese medicine treatment because of poor prognosis. After approximately 2 years of treatment, recurrent hepatic tumor and omentum metastasis have been found in complete regression. The patient remains alive over 31 months after relapse.

Cetuximab and Cisplatin Show Different Combination Effect in Nasopharyngeal Carcinoma Cells Lines via Inactivation of EGFR/AKT Signaling Pathway

Nasopharyngeal carcinoma (NPC) is a common malignant cancer in South China. Cisplatin is a classical chemotherapeutic employed for NPC treatment. Despite the use of cisplatin-based concurrent chemoradiotherapy, distant failure still confuses clinicians and the outcome of metastatic NPC remains disappointing. Hence, a potent systemic therapy is needed for this cancer. Epidermal growth factor receptor (EGFR) represents a promising new therapeutic target in cancer. We predicted that combining the conventional cytotoxic drug cisplatin with the novel molecular-targeted agent cetuximab demonstrates a strong antitumor effect on NPC cells. In this study, we selected HNE1 and CNE2 cells, which have been proved to possess different EGFR expression levels, to validate our conjecture. The two-drug regimen showed a significant synergistic effect in HNE1 cells but an additive effect in CNE2 cells. Our results showed that cisplatin-induced apoptosis was significantly enhanced by cetuximab in the high EGFR-expressing HNE1 cells but not in CNE2 cells. Further molecular mechanism study indicated that the EGFR/AKT pathway may play an important role in cell apoptosis via the mitochondrial-mediated intrinsic pathway and lead to the different antitumor effects of this two-drug regimen between HNE1 and CNE2 cells. Thus, the regimen may be applied in personalized NPC treatments.

Quinolone-indolone conjugate induces apoptosis by inhibiting the EGFR-STAT3-HK2 pathway in human cancer cells

The epidermal growth factor receptor (EGFR) is involved in the proliferation of human tumors and is an effective target for the treatment of cancer. In the present study, a novel quinolone-indolone conjugate, QIC1 [9-Fluoro-3,7-dihydro-3-methyl-10-(4-methyl -1-piperazinyl) -6-(2-oxo-1,2-dihydro-indol-3-ylidenemethyl) -7-oxo-2H-(1,4) oxazino(2,3,4-ij)quinoline], which targeted EGFR, was synthesized in order to investigate the anticancer activity and the potential mechanisms underlying the effect of this compound in human cancer cells. Using MTT assays it was observed that QIC1 inhibited the growth of HepG2 human hepatoma cells, MCF7 human breast cancer cells, HeLa human cervical cancer cells and A549 human lung adenocarcinoma cells. QIC1 arrested cell cycle progression at the G2/M phase in HepG2 cells. QIC1 inhibited the synthesis of DNA in A549 cells. In addition, it resulted in cell apoptosis, in association with increased expression of Bax and reduced expression of Bcl-2. Further analyses demonstrated that QIC1 attenuated the activity of EGFR, and the downstream signal transducer and activator of transcription 3 (STAT3)-mediated hexokinase II (HK2) signaling pathways. Furthermore, QIC1 exhibited antiproliferative effects in MCF7/DOX human doxorubicin-resistant breast cancer cells and also enhanced the anticancer activity of doxorubicin in these cells. In conclusion, the inhibition of proliferation and the induction of apoptosis was associated with reduced expression of phospho-EGFR-phospho-STAT3-HK2. The present results suggest a potential role for QIC1 in the treatment of human cancer.