Synergistic suppression of noscapine and conventional chemotherapeutics on human glioblastoma cell growth

Advances in glioblastoma multiforme: Integrating therapy and pathology perspectives

Glioblastoma, a highly lethal form of brain cancer, is characterized by its aggressive growth and resistance to conventional treatments, often resulting in limited survival. The response to therapy is notably influenced by various patient-specific genetic factors, underscoring the disease's complexity. Despite the utilization of diverse treatment modalities such as surgery, radiation, and chemotherapy, many patients experience local relapse, emphasizing the critical need for improved therapeutic strategies to effectively target these formidable tumors. Recent years have witnessed a surge in interest in natural products derived from plants, particularly alkaloids, for their potential anticancer effects. Alkaloids have shown promise in cancer chemotherapy by selectively targeting crucial signaling pathways implicated in tumor progression and survival. Specifically, they modulate the NF-κB and MAPK pathways, resulting in reduced tumor growth and altered gene expression across various cancer types. Additionally, alkaloids exhibit the capacity to induce cell cycle arrest, further impeding tumor proliferation in several malignancies. This review aims to delineate recent advances in understanding the pathology of glioblastoma multiforme (GBM) and to explore the potential therapeutic implications of alkaloids in managing this deadly disease. By segregating discussions on GBM pathology from those on alkaloid-based therapies, we provide a structured overview of the current challenges in GBM treatment and the promising opportunities presented by alkaloid-based interventions. Furthermore, we briefly discuss potential future directions in GBM research and therapy beyond alkaloids, including emerging treatment modalities or areas of investigation that hold promise for improving patient outcomes. In conclusion, our efforts offer hope for enhanced outcomes and improved quality of life for GBM patients through alkaloid-based therapies. By integrating insights from pathology and therapeutic perspectives, we underscore the significance of a comprehensive approach in addressing this devastating disease.

Evaluation of the Effects of Opium on the Expression of SOX2 and OCT4 in Wistar Rat Bladder

BACKGROUND

Bladder cancer is a malignancy greatly affected by behavioral habits. The aim of this study was to examine the effect of opium on changes in the expression of OCT4 and SOX2 in the bladder tissue of rats.

METHOD

Thirty six rats were divided into six groups: 24 rats in the addicted group received morphine and opium for 4 months with 12 rats in the control group. Blood testing was done for the evaluation of CBC, MDA, and TAC. The bladder tissue was removed and checked by histopathological examination. All total RNA was extracted, then cDNAs were synthesized and the OCT4 and SOX2 gene expressions were evaluated by Real-time PCR.

RESULTS

The OCT4 mRNA expression level in the opium group of rats was significantly increased compared to the control group (13.5 and 6.8 fold in males and females respectively). Also, in the morphine group, similar augmentation was detected (3.8 and 6.7 fold in males and females respectively). The SOX2 mRNA over-expression level was seen in the morphine group of both genders as compared to the control group (3.7 and 4.2 fold in male and female respectively) but in the opium group, enhancement of mRNA level was seen only in males (6.6 fold). Opium increases both OCT4 and SOX2 expression more than morphine in male rats, but in female rats, SOX2 is increased more by morphine.

CONCLUSION

Over expression of OCT4 and SOX2 was observed in rats treated with opium and morphine. Increased OCT4 and SOX2 expression was seen in opium-treated male rats, but in female rats, SOX2 was increased more by morphine.

Substrate-directed Synthesis of Isocoumarin and 3-Ylidenephthalide Conjugated Noscapinoids and their Antiproliferative Activities

A series of new noscapinoids designed; synthesized and assessed whether its 3-ylidenephthalide and isocoumarin conjugates improved cytotoxicity. Cu-catalysed Sonogashira coupling of N-propargyl noscapine with 2-bromobenzoic acids followed by in-situ substrate-directed 5-exo-dig or 6-endo-dig cyclization produced 3-ylidenephthalide 6 a-6 f and isocoumarin 7 a-7 h analogues in very good yields. In comparison to the lead drug, noscapine, all the newly synthesised derivatives exhibited strong cytotoxic potential in vitro with IC₅₀ ranging from 5.4 μM to 39.5 μM across the evaluated panel of cancer cell lines, without harming normal cells (IC₅₀ >300 μM).

Integration of phytotherapy and chemotherapy: Recent advances in anticancer molecular pathways

Cancer is a disease characterized by abnormal and uncontrolled growth of cells, leading to invasion and metastasis to other tissues. Chemotherapy drugs are some of the primary treatments for cancer, which could detrimentally affect the cancer cells by various molecular mechanisms like apoptosis and cell cycle arrest. These treatment lines have always aligned with side effects and drug resistance. Due to their anticancer effects, medicinal herbs and their active derivative compounds are being profoundly used as complementary treatments for cancer. Many studies have shown that herbal ingredients exert antitumor activities and immune-modulation effects and have fewer side effects. On the other hand, combining phytotherapy and chemotherapy, with their synergistic effects, has gained much attention across the medical community. This review article discussed the therapeutic effects of essential herbal active ingredients combined with chemotherapeutic drugs in cancer therapy. To write this article, PubMed and Scopus database were searched with the keywords "Cancer," "Combination," "Herbal," "Traditional," and "Natural." After applying inclusion/exclusion criteria, 110 articles were considered. The study shows the anticancer effects of the active herbal ingredients by inducing apoptosis and cell cycle arrest in cancer cells, especially with a chemotherapeutic agent. This study also indicates that herbal compounds can reduce side effects and dosage, potentiate anticancer responses, and sensitize cancer cells to chemotherapy drugs.

Natural products as chemo-radiation therapy sensitizers in cancers

Cancer is a devastating disease and is the second leading cause of death worldwide. Surgery, chemotherapy (CT), and/or radiation therapy (RT) are the treatment of choice for most advanced tumors. Unfortunately, treatment failure due to intrinsic and acquired resistance to the current CT and RT is a significant challenge associated with poor patient prognosis. There is an urgent need to develop and identify agents that can sensitize tumor cells to chemo-radiation therapy (CRT) with minimal cytotoxicity to the healthy tissues. While many recent studies have identified the underlying molecular mechanisms and therapeutic targets for CRT failure, using small molecule inhibitors to chemo/radio sensitize tumors is associated with high toxicity and increased morbidity. Natural products have long been used as chemopreventive agents in many cancers. Combining many of these compounds with the standard chemotherapeutic agents or with RT has shown synergistic effects on cancer cell death and overall improvement in patient survival. Based on the available data, there is strong evidence that natural products have a robust therapeutic potential along with CRT and their well-known chemopreventive effects in many solid tumors. This review article reports updated literature on different natural products used as CT or RT sensitizers in many solid tumors. This is the first review discussing CT and RT sensitizers together in cancer.

Noscapine, an Emerging Medication for Different Diseases: A Mechanistic Review

Noscapine is a benzylisoquinoline alkaloid isolated from poppy extract, used as an antitussive since the 1950s, and has no addictive or euphoric effects. Various studies have shown that noscapine has excellent anti-inflammatory effects and potentiates the antioxidant defences by inhibiting nitric oxide (NO) metabolites and reactive oxygen species (ROS) levels and increasing total glutathione (GSH). Furthermore, noscapine has indicated antiangiogenic and antimetastatic effects. Noscapine induces apoptosis in many cancerous cell types and provides favourable antitumour activities and inhibitory cell proliferation in solid tumours, even drug-resistant strains, via mitochondrial pathways. Moreover, this compound attenuates the dynamic properties of microtubules and arrests the cell cycle in the G2/M phase. Noscapine can reduce endothelial cell migration in the brain by inhibiting endothelial cell activator interleukin 8 (IL-8). In fact, this study aimed to elaborate on the possible mechanisms of noscapine against different disorders.

Biological and pharmacological activities of noscapine: Focusing on its receptors and mechanisms

Noscapine has been mentioned as one of the effective drugs with potential therapeutic applications. With few side effects and amazing capabilities, noscapine can be considered different from other opioids-like structure compounds. Since 1930, extensive studies have been conducted in the field of pharmacological treatments from against malaria to control cough and cancer treatment. Furthermore, recent studies have shown that noscapine and some analogues, like 9-bromonoscapine, amino noscapine, and 9-nitronoscapine, can be used to treat polycystic ovaries syndrome, stroke, and other diseases. Given the numerous results presented in this field and the role of different receptors in the therapeutic effects of noscapine, we aimed to review the properties, therapeutic effects, and the role of receptors in the treatment of noscapine.

Harmine Augments the Cytotoxic and Anti-invasive Potential of Temozolomide Against Glioblastoma Multiforme Cells

Background: Glioblastoma multiforme (GBM) is considered the deadliest human cancer. Temozolomide is now a part of postresection standard chemotherapy for this type of cancer. Unfortunately, resistance to temozolomide is a major obstacle to treatment success. Combination therapy with natural anticancer agents increases the activity of temozolomide against cancer cells. Objectives: This study aimed to assess the effects of temozolomide in combination with harmine against GBM cells. Methods: Cancer cells were treated with temozolomide and/or harmine. After 24, 48, 72, and 96 h, the viability of the cells was assessed by the MTT test. The combination index and dose reduction index were determined by CompuSyn software. Tumor invasion potential was investigated by evaluating cell migration, invasion, and adhesion. The real-time PCR technique was done to study the expression pattern of two genes involved in cancer cell invasion. Statistical analysis was performed using one-way analysis of variance and Tukey’s post-hoc test, and differences were considered non-significant at P > 0.05. Results: After treatment with temozolomide, cell viability showed a concentration- and time-dependent decrease, and the cells’ survival rate decreased. The combination of temozolomide and harmine had a synergistic effect. Also, temozolomide and/or harmine treatment decreased cancer cells’ migration, invasion, and adhesion potentials, as well as the expression of metalloproteinases 2 and 9 in T98G cells. Conclusions: The combination of temozolomide and harmine can be promising for the successful treatment of GBM.

Chemical diversity of dietary phytochemicals and their mode of chemoprevention

Despite the advancement in prognosis, diagnosis and treatment, cancer has emerged as the second leading cause of disease-associated death across the globe. With the remarkable application of synthetic drugs in cancer therapy and the onset of therapy-associated adverse effects, dietary phytochemicals have been materialized as potent anti-cancer drugs owing to their antioxidant, apoptosis and autophagy modulating activities. With dynamic regulation of apoptosis and autophagy in association with cell cycle regulation, inhibition in cellular proliferation, invasion and migration, dietary phytochemicals have emerged as potent anti-cancer pharmacophores. Dietary phytochemicals or their synthetic analogous as individual drug candidates or in combination with FDA approved chemotherapeutic drugs have exhibited potent anti-cancer efficacy. With the advancement in cancer therapeutics, dietary phytochemicals hold high prevalence for their use as precision and personalized medicine to replace conventional chemotherapeutic drugs. Hence, keeping these perspectives in mind, this review focuses on the diversity of dietary phytochemicals and their molecular mechanism of action in several cancer subtypes and tumor entities. Understanding the possible molecular key players involved, the use of dietary phytochemicals will thrive a new horizon in cancer therapy.

Octamer transcription factor-1 induces the Warburg effect via up-regulation of hexokinase 2 in non-small cell lung cancer

Reprogramming of energy metabolism is a hallmark of cancer which is prevalent worldwide. Octamer transcription factor-1 (OCT1) is a well-known transcription factor. However, the role of OCT1 in metabolism remodeling has not been well defined. In the present study, we found that OCT1 was up-regulated in non-small cell lung cancer (NSCLC) and correlated with poor patient survival. Further data identified that OCT1 increased glycolysis flux, promoting proliferation in lung cancer cells. Mechanistically, OCT1 facilitated the aerobic glycolysis and cell proliferation via up-regulation of hexokinase 2 (HK2), a crucial enzyme of the Warburg effect. Hence, our findings indicate that, in NSCLC, high levels of OCT1 contribute to the Warburg effect through up-regulation of HK2, linking up the OCT1/HK2 axis and cancer progression, which provide a potential biomarker and therapeutic target for NSCLC treatment.

Cytotoxic and chemosensitizing effects of glycoalkaloidic extract on 2D and 3D models using RT4 and patient derived xenografts bladder cancer cells

Glycoalkaloids have been widely demonstrated as potential anticancer agents. However, the chemosensitizing effect of these compounds with traditional chemotherapeutic agents has not been explored yet. In a quest for novel effective therapies to treat bladder cancer (BC), we evaluated the chemosensitizing potential of glycoalkaloidic extract (GE) with cisplatin (cDDP) in RT4 and PDX cells using 2D and 3D cell culture models. Additionally, we also investigated the underlying molecular mechanism behind this effect in RT4 cells. Herein, we observed that PDX cells were highly resistant to cisplatin when compared to RT4 cells. IC50 values showed at least 2.16-folds and 1.4-folds higher in 3D cultures when compared to 2D monolayers in RT4 cells and PDX cells, respectively. GE + cDDP inhibited colony formation (40%) and migration (28.38%) and induced apoptosis (57%) in RT4 cells. Combination therapy induced apoptosis by down-regulating the expression of Bcl-2 (p < 0.001), Bcl-xL (p < 0.001) and survivin (p < 0.01), and activating the caspase cascade in RT4 cells. Moreover, decreased expression of MMP-2 and 9 (p < 0.01) were observed with combination therapy, implying its effect on cell invasion/migration. Furthermore, we used 3D bioprinting to grow RT4 spheroids using sodium alginate-gelatin as a bioink and evaluated the effect of GE + cDDP on this system. Cell viability assay showed the chemosensitizing effect of GE with cDDP on bio-printed spheroids. In summary, we showed the cytotoxicity effect of GE on BC cells and also demonstrated that GE could sensitize BC cells to chemotherapy.

Drug Repositioning Screen on a New Primary Cell Line Identifies Potent Therapeutics for Glioblastoma

Glioblastoma is a malignant brain cancer with limited treatment options and high mortality rate. While established glioblastoma cell line models provide valuable information, they ultimately lose most primary characteristics of tumors under long-term serum culture conditions. Therefore, established cell lines do not necessarily recapitulate genetic and morphological characteristics of real tumors. In this study, in line with the growing interest in using primary cell line models derived from patient tissue, we generated a primary glioblastoma cell line, KUGBM8 and characterized its genetic alterations, long term growth ability, tumor formation capacity and its response to Temozolomide, the front-line chemotherapy utilized clinically. In addition, we performed a drug repurposing screen on the KUGBM8 cell line to identify FDA-approved agents that can be incorporated into glioblastoma treatment regimen and identified Topotecan as a lead drug among 1,200 drugs. We showed Topotecan can induce cell death in KUGBM8 and other primary cell lines and cooperate with Temozolomide in low dosage combinations. Together, our study provides a new primary cell line model that can be suitable for both in vitro and in vivo studies and suggests that Topotecan can offer promise as a therapeutic approach for glioblastoma.

A Combinational Approach Towards Treatment of Breast Cancer: an Analysis of Noscapine-Loaded Polymeric Nanoparticles and Doxorubicin

Our aim in this study was to clarify the combination anticancer effect of Noscapine (Nos) loaded in a polymeric nanocarrier with Doxorubicin (Dox) on breast cancer cells. Nanoprecipitation method was used to prepare methoxy polyethylene glycol (mPEG), poly lactic-co-glycolic acid (PLGA) nanoparticles (NPs) containing Nos. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) were used to characterize the prepared Nos NPs. The anticancer activity of Nos NPs alone and in combination with Dox was assessed on 4T1 breast cancer cell line and in mice model. Spherical-shaped Nos NPs were prepared, with size of 101 ± 4.80 nm and zeta potential of - 15.40 ± 1 mV. Fourier transform infrared (FTIR) spectroscopy results demonstrated that Nos chemical structure was kept stable during preparation process. However, differential scanning calorimetric (DSC) thermogram proved that crystalline state of Nos changed to amorphous state in Nos NPs. The entrapment efficacy % (EE%) and drug loading % (DL%) of Nos NPs were about 87.20 ± 3.50% and 12.50 ± 2.30%, respectively. Synergistic anticancer effects of Nos both in free form (in hydrochloride form, Nos HCl) and Nos NPs form with Dox hydrochloride (Dox HCl) were observed on 4T1 cells. Combination of Nos NPs and Dox HCl inhibited tumor growth (68.50%) in mice more efficiently than Nos NPs (55.10%) and Dox HCl (32%) alone. Immunohistochemical (IHC) analysis of the tumor tissues confirmed antiangiogenic effect of Nos NPs. The findings highlighted efficacy of Nos NPs alone and in combination with Dox HCl on breast cancer tumors.

Molecular mechanisms of cell death induced in glioblastoma by experimental and antineoplastic drugs: New and old drugs induce apoptosis in glioblastoma

Glioblastoma multiforme (GBM) is one of the most aggressive astrocytic tumors; it is resistant to most chemotherapeutic agents currently available and is associated with a poor patient survival. Thus, the development of new anticancer compounds is urgently required. Herein, we studied the molecular mechanisms of cell death induced by the experimental drugs resveratrol and MG132 or the antineoplastic drugs cisplatin and etoposide on a human GBM cell line (D54) and on primary cultured mouse astrocytes (PCMAs). Caspases, Bcl-2, inhibitors of apoptosis proteins (IAP) family members, and p53 were identified as potential molecular targets for these drugs. All drugs had a cytotoxic effect on D54 cells and PCMAs, with a similar inhibitory concentration (IC₅₀) after 24 h. However, MG132 and cisplatin were more effective to induce apoptosis and autophagy than resveratrol and etoposide. Cell death by apoptosis involved the activation of caspases-3/7, -8, and -9, increased lysosomal permeability, LC3 lipidation, poly-(ADP-ribose) polymerase (PARP)-1 fragmentation, and a differential expression of genes related with apoptosis and autophagy like Mcl-1, Survivin, Noxa, LC3, and Beclin. In addition, apoptosis activation was partially dependent on p53 activation. Since experimental and antineoplastic drugs yielded similar results, further work is required to justify their use in clinical protocols.

Involvement of Phosphatase and Tensin Homolog in Cyclin-Dependent Kinase 4/6 Inhibitor-Induced Blockade of Glioblastoma

Dysregulation of retinoblastoma (Rb) signaling pathway have been established as a requirement for glioblastoma (GBM) initiation and progression, which suggests that blockade of CDK4/6-Rb signaling axis for GBM treatment. Palbociclib, a selective inhibitor of the cyclin-dependent kinases CDK4/6, has been applied for breast cancer treatment. However, its efficacy against glioblastoma has not been well clarified. Here, effects of CDK4/6 inhibitors on various kinds of GBM cell lines are investigated and the functional mechanisms are identified. Data showed that cells with diverse PTEN status respond to palbociclib differently. Gain-of-function and loss-of-function studies indicated that PTEN enhanced the sensitivity of GBM cells to palbociclib in vitro and in vivo, which was associated with suppressions of Akt and ERK signaling and independent of Rb signaling inhibition. Hence, our findings support that palbociclib selectively

Chemosensitizing Effect of Cernumidine Extracted from Solanum cernuum on Bladder Cancer Cells in Vitro

Cernumidine (CER) is a guanidinic alkaloid isolated from Solanum cernuum leaves. In this work, we investigated the cytotoxicity, chemosensitizing effect of cernumidine to cisplatin (cDDP) and the possible mechanism of action of the combination on bladder cancer cells. Cernumidine showed cytotoxicity and could sensitize bladder cancer cells to cisplatin. The combination of CER+cDDP inhibited cell migration on T24 cells. CER+cDDP down-regulated MMP-2/9 and p-ERK1/2, while it increased EGFR activity corroborating the observed cell migration inhibition. Down-regulation of Bcl-2 and up-regulation pro-apoptotic Bax and further depletion of the mitochondrial membrane potential (ΔΨm) indicates that mitochondria play a central role in the combination treatment inducing the mitochondrial signaling pathway of apoptosis in T24 cells. Our data showed that the alkaloid cernumidine is worthy of further studies as a chemosensitizing agent to be used in complementary chemotherapy.

Temozolomide and tranilast synergistic antiproliferative effect on human glioblastoma multiforme cell line (U87MG)

Background: Glioblastoma multiforme (GBM) is the most malignant primary brain tumor. Temozolomide (TMZ) is a chemotherapeutic agent that has been used in GBM treatment. Resistance to TMZ is a major obstacle to successful GBM treatment. The aim of the present study was to investigate the effect of TMZ and tranilast on human GBM cell line (U87MG). Methods: In this in vitro experimental study, the effect of TMZ and tranilast on cell proliferation was measured using the MTT assay. Median effect analysis was performed to determine the TMZ and tranilast interaction. Lactate dehydrogenase assay was used to determine TMZ and tranilast cytotoxicity. Cell fluorescent staining and real-time PCR were used for apoptosis evaluation. The effect of TMZ and tranilast on U87MG nitric oxide (NO) production was evaluated by Griess assay. Results: TMZ and tranilast had a significant dose- and time-dependent inhibitory effect on cell proliferation. The mean combination index values represented a synergistic effect, and dose reduction index values suggested the advantages of reducing the toxicity, adverse effects, and drug resistance in combination of TMZ and tranilast. Apoptosis cell death was induced by TMZ and/or tranilast in cells. TMZ and tranilast reduced NO. production in cells. Conclusion: TMZ and tranilast combination inhibited the GBM cells growth effectively.

Noscapine, a Non-addictive Opioid and Microtubule-Inhibitor in Potential Treatment of Glioblastoma

Noscapine is a phthalide isoquinoline alkaloid that easily traverses the blood brain barrier and has been used for years as an antitussive agent with high safety. Despite binding opioid receptors, noscapine lacks significant hypnotic and euphoric effects rendering it safe in terms of addictive potential. In 1954, Hans Lettré first described noscapine as a mitotic poison. The drug was later tested for cancer treatment in the early 1960's, yet no effect was observed likely as a result of its short biological half-life and limited water solubility. Since 1998, it has regained interest thanks to studies from Emory University, which showed its anticancer activity in animal models with negligible toxicity. In contrast to other microtubule-inhibitors, noscapine does not affect the total intracellular tubulin polymer mass. Instead, it forces the microtubules to spend an increased amount of time in a paused state leading to arrest in mitosis and subsequently inducing mitotic slippage/mitotic catastrophe/apoptosis. In experimental models, noscapine does not induce peripheral neuropathy, which is common with other microtubule inhibitors. Noscapine also inhibits tumor growth and enhances cancer chemosensitivity via selective blockage of NF-κB, an important transcription factor in glioblastoma pathogenesis. Due to their anticancer activities and high penetration through the blood-brain barrier, noscapine analogues strongly deserve further study in various animal models of glioblastoma as potential candidates for future patient therapy.

Targeting breast cancer cells with a CuInS2/ZnS quantum dot-labeled Ki-67 bioprobe

The aim of the present study was to develop a water-soluble biomarker for the detection of breast cancer using quantum dots (QDs) conjugated to Ki-67, a nuclear protein associated with the cell cycle. Ki-67 is also a marker of cell proliferation, with expression levels categorizing good and poor prognosis in invasive breast cancer. Ki-67 is a clinically used biomarker for breast cancer diagnosis, treatment and prognosis. Owing to the optical and chemical advantages of QDs, QD-based nanotechnology may aid the construction of a biomedical imaging platform for the study of cancer cell behavior. In the present study, a biomarker was prepared by employing the water-soluble CuInS₂/ZnS QDs conjugated to an anti-Ki-67 monoclonal antibody to detect Ki-67 expression in breast cancer. The QDs, which were hydrophobic and coated with octadecylamine, were encapsulated with an amphiphilic biocompatible centipede-like polymer, and then conjugated to anti-Ki-67 monoclonal antibodies (QD-Ki-67 probes). The QD-Ki-67 probes retained the original optical properties of the unadorned QDs and did not exhibit distinct toxic side effects in in vitro cytotoxicity experiments. Therefore, this CuInS₂/ZnS QD-labeled bioprobe, with a high quantum yield and low cytotoxicity, is a promising candidate for bioimaging and may be used as a cell label.

Temozolomide-Mediated Apoptotic Death Is Improved by Thymoquinone in U87MG Cell Line

Apoptosis induction of cancer cells can be an appropriate strategy by which chemotherapeutic agents kill tumor cells. The aim of the present study was to investigate the effect of temozolomide and thymoquinone combination on apoptotic pathway of human glioblastoma multiforme cell line (U87MG). U87MG cells were cultured, treated with temozolomide and thymoquinone, and cell proliferation was measured. Apoptosis cell death and its possible mechanism were investigated by various methods. Combination of temozolomide and thymoquinone had a synergistic effect on cells viability. Thymoquinone intensified the temozolomide-induced apoptosis. Combination of temozolomide and thymoquinone can be a good strategy for treatment of glioblastoma.

Phytomedicine-Modulating oxidative stress and the tumor microenvironment for cancer therapy

In spite of the current advances and achievements in systems biology and translational medicinal research, the current strategies for cancer therapy, such as radiotherapy, targeted therapy, immunotherapy and chemotherapy remain palliative or unsatisfactory due to tumor metastasis or recurrence after surgery/therapy, drug resistance, adverse side effects, and so on. Oxidative stress (OS) plays a critical role in chronic/acute inflammation, carcinogenesis, tumor progression, and tumor invasion/metastasis which is also attributed to the dynamic and complex properties and activities in the tumor microenvironment (TME). Re-educating or reprogramming tumor-associated stromal or immune cells in the TME provides an approach for restoring immune surveillance impaired by disease in cancer patients to increase overall survival and reduce drug resistance. Herbal medicines or plant-derived natural products have historically been a major source of anti-cancer drugs. Delving into the lore of herbal medicine may uncover new leads for anti-cancer drugs. Phytomedicines have been widely documented to directly or indirectly target multiple signaling pathways and networks in cancer cells. A combination of anti-cancer drugs and polypharmacological plant-derived extracts or compounds may offer a significant advantage in sensitizing the efficacy of monotherapy and overcoming drug-induced resistance in cancer patients. This review introduces several phytochemicals and phytoextracts derived from medicinal plants or dietary vegetables that have been studied for their efficacy in preclinical cancer models. We address the underlying modes of action of induction of OS and deregulation of TME-associated stromal cells, mediators and signaling pathways, and reference the related clinical investigations that look at the single or combination use of phytochemicals and phytoextracts to sensitize anti-cancer drug effects and/or overcome drug resistance.

Noscapine chemosensitization enhances docetaxel anticancer activity and nanocarrier uptake in triple negative breast cancer

Chemosensitization and enhanced delivery to solid tumor are widely explored strategies to augment the anticancer efficacy of existing chemotherapeutics agents. The aim of current research was to investigate the role of low dose Noscapine (Nos) in potentiating docetaxel cytotoxicity and enhancing tumor penetration of nanocarriers. The objectives are; (1) To evaluate the chemo-sensitizing effect of Nos in combination with docetaxel (DTX), and to elucidate the possible mechanism (2) To investigate the effect of low dose Nos on tumor stroma and enhancing nanocarrier uptake in triple negative breast cancer (TNBC) bearing nude mice. Cytotoxicity and flow cytometry analysis of DTX in Nos (4µM) pre-treated MDA-MB-231 cells showed 3.0-fold increase in cell killing and 30% increase in number of late apoptotic cells, respectively. Stress transducer p38 phosphorylation was significantly upregulated with Nos exposure. DTX showed remarkable downregulation in expression of bcl-2, survivin and pAKT in Nos pre-treated MDA-MB-231 cells. Nos pre-sensitization significantly (p<0.02) enhanced the anti-migration effect of DTX. In vivo studies in orthotopic TNBC tumor bearing mice showed marked reduction in tumor collagen-I levels and significantly (p<0.03) higher intra-tumoral uptake of coumarin-6 loaded PEGylated liposomes (7-fold) in Nos treated group. Chemo-sensitization and anti-fibrotic effect of Nos could be a promising approach to increase anticancer efficacy of DTX which can be used for other nanomedicinal products.

Delivery of a drug cache to glioma cells overexpressing platelet-derived growth factor receptor using lipid nanocarriers

AIM

Glioblastoma multiforme is a devastating disease with no curative options due to the difficulty in achieving sufficient quantities of effective chemotherapies into the tumor past the blood-brain barrier. Micelles loaded with temozolomide (TMZ) were designed to increase the delivery of this drug into the brain.

MATERIALS & METHODS

pH-responsive micelles composed of distearoyl phosphoethanolamine-PEG-2000-amine and N-palmitoyl homocysteine were surface-functionalized with PDGF peptide and Dylight 680 fluorophore.

RESULTS & CONCLUSION

PDGF-micelles containing TMZ have specific uptake and increased killing in glial cells compared with untargeted micelles. In vivo studies demonstrated selective accumulation of PDGF-micelles containing TMZ in orthotopic gliomas implanted in mice. Targeted micelle-based drug carrier systems hold potential for delivery of a wide variety of hydrophobic drugs thereby reducing its systemic toxicity.

Hypoxia-inducible factor-1 and associated upstream and downstream proteins in the pathophysiology and management of glioblastoma

Glioblastoma multiforme (GBM) is a highly aggressive brain tumor with an exceptionally poor patient outcome despite aggressive therapy including surgery, radiation, and chemotherapy. This aggressive phenotype may be associated with intratumoral hypoxia, which probably plays a key role in GBM tumor growth, development, and angiogenesis. A key regulator of cellular response to hypoxia is the protein hypoxia-inducible factor–1 (HIF-1). An examination of upstream hypoxic and nonhypoxic regulation of HIF-1 as well as a review of the downstream HIF-1– regulated proteins may provide further insight into the role of this transcription factor in GBM pathophysiology. Recent insights into upstream regulators that intimately interact with HIF-1 could provide potential therapeutic targets for treatment of this tumor. The same is potentially true for HIF-1–mediated pathways of glycolysis-, angiogenesis-, and invasion-promoting proteins. Thus, an understanding of the relationship between HIF-1, its upstream protein regulators, and its downstream transcribed genes in GBM pathogenesis could provide future treatment options for the care of patients with these tumors.

The Noscapine Chronicle: A Pharmaco-Historic Biography of the Opiate Alkaloid Family and its Clinical Applications

Given its manifold potential therapeutic applications and amenability to modification, noscapine is a veritable "Renaissance drug" worthy of commemoration. Perhaps the only facet of noscapine's profile more astounding than its versatility is its virtual lack of side effects and addictive properties, which distinguishes it from other denizens of Papaver somniferum. This review intimately chronicles the rich intellectual and pharmacological history behind the noscapine family of compounds, the length of whose arms was revealed over decades of patient scholarship and experimentation. We discuss the intriguing story of this family of nontoxic alkaloids, from noscapine's purification from opium at the turn of the 19th century in Paris to the recent torrent of rationally designed analogs with tremendous anticancer potential. In between, noscapine's unique pharmacology; impact on cellular signaling pathways, the mitotic spindle, and centrosome clustering; use as an antimalarial drug and cough suppressant; and exceptional potential as a treatment for polycystic ovarian syndrome, strokes, and diverse malignancies are catalogued. Seminal experiments involving some of its more promising analogs, such as amino-noscapine, 9-nitronoscapine, 9-bromonoscapine, and reduced bromonoscapine, are also detailed. Finally, the bright future of these oftentimes even more exceptional derivatives is described, rounding out a portrait of a truly remarkable family of compounds.

Quercetin sensitizes human glioblastoma cells to temozolomide in vitro via inhibition of Hsp27

AIM

Quercetin is an effective Hsp27 inhibitor and has been reported to facilitate tumor cell apoptosis. The aim of this study was to investigate whether quercetin could sensitize human glioblastoma cells to temozolomide (TMZ) in vitro.

METHODS

Both U251 and U87 human glioblastoma cells were treated with quercetin and/or TMZ for 48 h. Cell viability was detected using the MTT assay. Cell apoptosis was analyzed with caspase-3 activity kits and flow cytometry. Hsp27 expression and phosphorylation were examined using Western blot analysis. RNA interference using Hsp27 siRNA oligos was performed to knock down the gene expression of Hsp27.

RESULTS

TMZ (200 or 400 μmol/L) alone effectively inhibited the viability of U251 and U87 cells. When combined with quercetin (30 μmol/L), TMZ (100 μmol/L) significantly inhibited the cell viability, and the inhibition of TMZ (200 and 400 μmol/L) was enhanced. TMZ or quercetin anole did not affect caspase-3 activity and cell apoptosis, while TMZ combined with quercetin significantly increased caspase-3 activity and induced cell apoptosis. TMZ anole significantly increased Hsp27 phosphorylation in U251 and U87 cells, while quercetin or Hsp27 siRNA oligos combined with TMZ attenuated TMZ-induced Hsp27 phosphorylation and significantly inhibited Hsp27 expression.

CONCLUSION

Combined treatment with TMZ and quercetin efficiently suppressed human glioblastoma cell survival in vitro.