Paclitaxel and Its Evolving Role in the Management of Ovarian Cancer

Combining TNFR2-Expressing Tregs and IL-6 as Superior Diagnostic Biomarkers for High-Grade Serous Ovarian Cancer Masses

We hypothesised that the inclusion of immunosuppressive and inflammatory biomarkers in HGSOC patients would improve the sensitivity and specificity of the preoperative marker prediction of malignancy in patients with ovarian masses. We tested a panel of 29 soluble immune factors by multiplex bead immunoassay and 16 phenotypic T cell markers by flow cytometry in pre-treatment blood samples from 66 patients undergoing surgery for suspected ovarian cancer or ovarian cancer risk reduction. The potential diagnostic utility of all parameters was explored using Volcano plots, principal component analysis (PCA) and receiver operator characteristic (ROC) analysis. We also assessed the effect of culturing PBMCs from 20 healthy donors in the presence of malignant ascites fluid. The combination of TNFR2⁺ Tregs and IL-6 in the pre-treatment blood of patients with advanced HGSOC effectively discriminated patients with benign or malignant ovarian masses. In vitro culturing of the PBMCs of healthy donors in malignant ascites promoted an increase in TNFR2-expressing Tregs, which were decreased following blockade with IL-6 or STAT3 activity. Pre-treatment serum IL-6 and peripheral blood TNFR2⁺ Tregs may be potential clinical biomarkers that can discriminate patients with malignant compared to benign ovarian cancer masses, and the relationship between IL-6 and TNFR2⁺ Treg is likely to be mediated via the STAT3 signalling pathway.

Predicting Prognosis and Platinum Resistance in Ovarian Cancer: Role of Immunohistochemistry Biomarkers

Ovarian cancer is a lethal reproductive tumour affecting women worldwide. The advancement in presentation and occurrence of chemoresistance are the key factors for poor survival among ovarian cancer women. Surgical debulking was the mainstay of systemic treatment for ovarian cancer, which was followed by a successful start to platinum-based chemotherapy. However, most women develop platinum resistance and relapse within six months of receiving first-line treatment. Thus, there is a great need to identify biomarkers to predict platinum resistance before enrolment into chemotherapy, which would facilitate individualized targeted therapy for these subgroups of patients to ensure better survival and an improved quality of life and overall outcome. Harnessing the immune response through immunotherapy approaches has changed the treatment way for patients with cancer. The immune outline has emerged as a beneficial tool for recognizing predictive and prognostic biomarkers clinically. Studying the tumour microenvironment (TME) of ovarian cancer tissue may provide awareness of actionable targets for enhancing chemotherapy outcomes and quality of life. This review analyses the relevance of immunohistochemistry biomarkers as prognostic biomarkers in predicting chemotherapy resistance and improving the quality of life in ovarian cancer.

Coding roles of long non-coding RNAs in breast cancer: Emerging molecular diagnostic biomarkers and potential therapeutic targets with special reference to chemotherapy resistance

Dysregulation of epigenetic mechanisms have been depicted in several pathological consequence such as cancer. Different modes of epigenetic regulation (DNA methylation (hypomethylation or hypermethylation of promotor), histone modifications, abnormal expression of microRNAs (miRNAs), long non-coding RNAs, and small nucleolar RNAs), are discovered. Particularly, lncRNAs are known to exert pivot roles in different types of cancer including breast cancer. LncRNAs with oncogenic and tumour suppressive potential are reported. Differentially expressed lncRNAs contribute a remarkable role in the development of primary and acquired resistance for radiotherapy, endocrine therapy, immunotherapy, and targeted therapy. A wide range of molecular subtype specific lncRNAs have been assessed in breast cancer research. A number of studies have also shown that lncRNAs may be clinically used as non-invasive diagnostic biomarkers for early detection of breast cancer. Such molecular biomarkers have also been found in cancer stem cells of breast tumours. The objectives of the present review are to summarize the important roles of oncogenic and tumour suppressive lncRNAs for the early diagnosis of breast cancer, metastatic potential, and chemotherapy resistance across the molecular subtypes.

Molecular Imaging of Oxygenation Changes during Immunotherapy in Combination with Paclitaxel in Triple Negative Breast Cancer

Hypoxia is a common feature of the tumor microenvironment, including that of triple-negative breast cancer (TNBC), an aggressive breast cancer subtype with a high five-year mortality rate. Using [18F]-fluoromisonidazole (FMISO) positron emission tomography (PET) imaging, we aimed to monitor changes in response to immunotherapy (IMT) with chemotherapy in TNBC. TNBC-tumor-bearing mice received paclitaxel (PTX) ± immune checkpoint inhibitors anti-programmed death 1 and anti-cytotoxic T-lymphocyte 4. FMISO-PET imaging was performed on treatment days 0, 6, and 12. Max and mean standard uptake values (SUVmax and SUVmean, respectively), histological analyses, and flow cytometry results were compared. FMISO-PET imaging revealed differences in tumor biology between treatment groups prior to tumor volume changes. 4T1 responders showed SUVmean 1.6-fold lower (p = 0.02) and 1.8-fold lower (p = 0.02) than non-responders on days 6 and 12, respectively. E0771 responders showed SUVmean 3.6-fold lower (p = 0.001) and 2.7-fold lower (p = 0.03) than non-responders on days 6 and 12, respectively. Immunohistochemical analyses revealed IMT plus PTX decreased hypoxia and proliferation and increased vascularity compared to control. Combination IMT/PTX recovered the loss of CD4+ T-cells observed with single-agent therapies. PET imaging can provide timely, longitudinal data on the TNBC tumor microenvironment, specifically intratumoral hypoxia, predicting therapeutic response to IMT plus chemotherapy.

Therapeutic potential of TRPM8 channels in cancer treatment

Cancer is a multifactorial process associated with changes in signaling pathways leading to cell cycle variations and gene expression. The transient receptor potential melastatin 8 (TRPM8) channel is a non-selective cation channel expressed in neuronal and non-neuronal tissues, where it is involved in several processes, including thermosensation, differentiation, and migration. Cancer is a multifactorial process associated with changes in signaling pathways leading to variations in cell cycle and gene expression. Interestingly, it has been shown that TRPM8 channels also participate in physiological processes related to cancer, such as proliferation, survival, and invasion. For instance, TRPM8 channels have an important role in the diagnosis, prognosis, and treatment of prostate cancer. In addition, it has been reported that TRPM8 channels are involved in the progress of pancreatic, breast, bladder, colon, gastric, and skin cancers, glioblastoma, and neuroblastoma. In this review, we summarize the current knowledge on the role of TRPM8 channels in cancer progression. We also discuss the therapeutic potential of TRPM8 in carcinogenesis, which has been proposed as a molecular target for cancer therapy.

Interplay between MAP kinases and tumor microenvironment: Opportunity for immunotherapy in pancreatic cancer

Pancreatic Ductal Adenocarcinoma (PDAC), commonly called pancreatic cancer, is aggressive cancer usually detected at a late stage, limiting treatment options with modest clinical responses. It is projected that by 2030, PDAC will be the second most common cause of cancer-related mortality in the United States. Drug resistance in PDAC is common and significantly affects patients' overall survival (OS). Oncogenic KRAS mutations are nearly uniform in PDAC, affecting over 90% of patients. However, effective drugs directed to target prevalent KRAS mutants in pancreatic cancer are not in clinical practice. Accordingly, efforts are continued on identifying alternative druggable target(s) or approaches to improve patient outcomes with PDAC. In most PDAC cases, the KRAS mutations turn-on the RAF-MEK-MAPK pathways, leading to pancreatic tumorigenesis. The MAPK signaling cascade (MAP4K→MAP3K→MAP2K→MAPK) plays a central role in the pancreatic cancer tumor microenvironment (TME) and chemotherapy resistance. The immunosuppressive pancreatic cancer TME is another unfavorable factor affecting the therapeutic efficacy of chemotherapy and immunotherapy. The immune checkpoint proteins (ICPs), including CTLA-4, PD-1, PD-L1, and PD-L2, are critical players in T cell dysfunction and pancreatic tumor cell growth. Here, we review the activation of MAPKs, a molecular trait of KRAS mutations and their impact on pancreatic cancer TME, chemoresistance, and expression of ICPs that could influence the clinical outcomes in PDAC patients. Therefore, understanding the interplay between MAPK pathways and TME could help to design rational therapy combining immunotherapy and MAPK inhibitors for pancreatic cancer treatment.

Simple Multifunctional PTX@Ce6 Nanomedicine for Eradicating Tumor in the Combination of Photodynamic Therapy and Metronomic Chemotherapy

Photodynamic therapy (PDT) is an effective treatment modality for various cancer types. However, tumor recurrence and metastasis stemming from residual cancer cells after PDT pose serious problems. In this study, a simple multifunctional PTX@Ce6 nanomedicine is prepared using a two-step reprecipitation method. In this core-shell nanostructure, the toxic paclitaxel (PTX) core is embedded into a nontoxic Ce6 shell. An ultralow dose of PTX (1 mg/kg) stimulates the differentiation of marrow-derived suppressor cells (MDSCs) into mature dendritic cells (DCs), resulting in the restoration of functions of tumor-specific CD8⁺ T cells and promotion of antitumor immune responses in vivo. Hence, the tumors in mice are eradicated with 100% tumor inhibition rate via combination therapy. Tumor recurrence and metastasis are also effectively inhibited. In addition, the combination therapy with PDT and metronomic chemotherapy based on core-shell PTX@Ce6 nanostructures shows high biosafety in treated mice. This study can aid in developing new cancer treatment modalities for eradicating tumors, preventing tumor recurrence and metastasis, and reducing the systemic side effects of therapy.

Evaluation of cytotoxicity, loading, and release activity of paclitaxel loaded-porphyrin based metal-organic framework (PCN-600)

Considering the inducement side impacts and precipitation of continual doses in conventional therapeutic treatments, there is an urgent need in the field of drug delivery for novel designs of biocompatible carriers with wide loading dimensions and particularly the ability to control their drug release. In this work, we succeeded in synthesizing an iron-based organic metal framework based on iron-porphyrin (PCN-600) through a solvothermal method to function as a drug delivery system (DDS). According to SEM results, PCN-600 crystals a hexagonal-rod shaped morphology with the length of 300 nm and width of 100-300 nm. As an anticancer drug, Paclitaxel (PTX) was successfully loaded into the porphyrin-based metal-organic framework (PCN-600) via in-situ encapsulation; the loading efficiency was measured to be about 87.3%. In addition, PTX-encapsulated PCN-600 displayed a controlled and sustained release for up to 24 h of release assessment at the physiological microenvironment of pH = 7.4.

Phytochemicals as Chemo-Preventive Agents and Signaling Molecule Modulators: Current Role in Cancer Therapeutics and Inflammation

Cancer is one of the deadliest non communicable diseases. Numerous anticancer medications have been developed to target the molecular pathways driving cancer. However, there has been no discernible increase in the overall survival rate in cancer patients. Therefore, innovative chemo-preventive techniques and agents are required to supplement standard cancer treatments and boost their efficacy. Fruits and vegetables should be tapped into as a source of compounds that can serve as cancer therapy. Phytochemicals play an important role as sources of new medication in cancer treatment. Some synthetic and natural chemicals are effective for cancer chemoprevention, i.e., the use of exogenous medicine to inhibit or impede tumor development. They help regulate molecular pathways linked to the development and spread of cancer. They can enhance antioxidant status, inactivating carcinogens, suppressing proliferation, inducing cell cycle arrest and death, and regulating the immune system. While focusing on four main categories of plant-based anticancer agents, i.e., epipodophyllotoxin, camptothecin derivatives, taxane diterpenoids, and vinca alkaloids and their mode of action, we review the anticancer effects of phytochemicals, like quercetin, curcumin, piperine, epigallocatechin gallate (EGCG), and gingerol. We examine the different signaling pathways associated with cancer and how inflammation as a key mechanism is linked to cancer growth.

Chemosensitivity of 3D Pancreatic Cancer Organoids Is Not Affected by Transformation to 2D Culture or Switch to Physiological Culture Medium

Organoids are increasingly used to investigate patient-specific drug responsiveness, but organoid culture is complex and expensive, and carried out in rich, non-physiological media. We investigated reproducibility of drug-responsiveness of primary cell cultures in 2D versus 3D and in conventional versus physiological cell culture medium. 3D pancreatic ductal adenocarcinoma organoid cultures PANCO09b and PANCO11b were converted to primary cell cultures growing in 2D. Transformed 2D cultures were grown in physiological Plasmax medium or Advanced-DMEM/F12. Sensitivity towards gemcitabine, paclitaxel, SN-38, 5-fluorouacil, and oxaliplatin was investigated by cell viability assays. Growth rates of corresponding 2D and 3D cultures were comparable. PANCO09b had a shorter doubling time in physiological media. Chemosensitivity of PANCO09b and PANCO11b grown in 2D or 3D was similar, except for SN-38, to which PANCO11b cultured in 3D was more sensitive (2D: 8.2 ×10^-3 ± 2.3 ×10^-3 vs. 3D: 1.1 ×10^-3 ± 0.6 ×10^-3, p = 0.027). PANCO09b and PANCO11b showed no major differences in chemosensitivity when cultured in physiological compared to conventional media, although PANCO11b was more sensitive to SN-38 in physiological media (9.8 × 10^-3 ± 0.7 × 10^-3 vs. 5.2 × 10^-3 ± 1.8 × 10^-3, p = 0.015). Collectively, these data indicate that the chemosensitivity of organoids is not affected by culture medium composition or culture dimensions. This implies that organoid-based drug screens can be simplified to become more cost-effective.

Recent Developments and Anticancer Therapeutics of Paclitaxel: An Update

Plants are a source of diverse classes of secondary metabolites with anticancer properties. Paclitaxel (Taxol) is an anticancer drug isolated from various Taxus species and is used as a chemotherapeutic agent against various cancers. The biosynthesis of paclitaxel is a complex pathway, making its total chemical synthesis commercially non-viable; hence, alternative novel sources - like plant cell culture and heterologous expression systems, are being investigated to overcome this issue. Advancements in the field of genetic engineering, microbial fermentation engineering, and recombinant techniques have significantly increased the achievable yields of paclitaxel. Indeed, paclitaxel selectively targets microtubules and causes cell cycle arrest in the G2/M phase, inducing a cytotoxic effect in a concentration and time-dependent manner. Innovative drug delivery formulations, like the development of albumin-bound nanoparticles, nano-emulsions, nano-suspensions, liposomes, and polymeric micelles, have been applied to enhance the delivery of paclitaxel to tumor cells. This review focuses on the production, biosynthesis, mechanism of action, and anticancer effects of paclitaxel.

Efficacy of platinum-based and non-platinum-based drugs on triple-negative breast cancer: meta-analysis

Background

Triple-negative breast cancer (TNBC), the subtype of breast cancer with the highest mortality rate, shows clinical characteristics of high heterogeneity, aggressiveness, easy recurrence, and poor prognosis, which is due to lack of expression of estrogen, progesterone receptor and human epidermal growth factor receptor 2. Currently, neoadjuvant chemotherapy (NAT) is still the major clinical treatment for triple-negative breast cancer. Chemotherapy drugs can be divided into platinum and non-platinum according to the presence of metal platinum ions in the structure. However, which kind is more suitable for treating TNBC remains to be determined.

Methods

The relevant randomized clinical trials (RCTs) that explore the effectiveness of chemotherapy regimens containing platinum-based drugs (PB) or platinum-free drugs (PF) in treating TNBC patients were retrieved through PubMed, EMBASE, Cochrane Library, CNKI, and other literature platforms, above research findings, were included in the meta-analysis. The incidence of overall remission rate (ORR), pathological complete remission rate (pCR), overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), and adverse events (AE) were compared between the two groups.

Results

In this study, 12 clinical trials with a total of 4580 patients were included in the analysis. First, the ORR in 4 RCTs was, PB vs PF = 52% vs 48% (RR = 1.05, 95% CI: 0.91–1.21, P = 0.48); the pCR in 5 RCTs was, PB vs PF = 48% vs 41% (RR = 1.38, 95% CI: 0.88–2.16, P = 0.17). CI: 0.88–2.16, P = 0.17; the other 2 RCTs reported significantly higher DFS and OS rates in the PB group compared with the PF group, with the combined risk ratio for DFS in the PB group RR = 0.22 (95% CI:0.06–0.82, P = 0.015); the combined risk ratio for DFS in the PF group RR = 0.15 (95% CI. 0.04–0.61, P = 0.008); OS rate: PB vs PF = 0.046 vs 0.003; secondly, 2 RCTs showed that for patients with BRCA-mutated TNBC, the pCR rate in the PB and PF groups was 18% vs 26%, 95% CI: 2.4–4.2 vs 4.1–5.1; meanwhile, the median subject in the PB group The median PFS was 3.1 months (95% CI: 2.4–4.2) in the PB group and 4.4 months (95% CI: 4.1–5.1) in the PC group; finally, the results of the clinical adverse effects analysis showed that platinum-containing chemotherapy regimens significantly increased the incidence of adverse effects such as thrombocytopenia and diarrhea compared with non-platinum regimens, while the incidence of adverse effects such as vomiting, nausea, and neutropenia was reduced. The incidence of adverse reactions was reduced.

Conclusion

Compared with non-platinum drugs, platinum drugs significantly improved clinical treatment effective indexes, such as PCR, ORR, PFS, DFS, and OS rate in the treatment of TNBC patients without BRCA mutant may cause more serious hematological adverse reactions. Accordingly, platinum-based chemotherapy should be provided for TNBC patients according to the patient's special details.

A method of isolating and analysing drugs from cancer cells for preclinical research

The presented paper describes a new isolation method of recovery and analysis of selected drugs developed for preclinical research. The method uses the RP-HPLC technique (in a single chromatographic separation) and serves the recovery and analysis of selected drugs from neoplastic cells. It enables the determination of cytostatics statins, fibrates, and pioglitazone. Chromatographic separations of the tested compounds were carried out on a Gemini-NX 5 µ C18 (4.6 × 150 mm i.d.) column, in a gradient system with a mobile phase consisting of ACN (0.1% TFA) and water (0.1% TFA) at ambient temperature. The separations were carried out at a flow of 1 ml/min and UV detection of 220 nm. The inter-day and intra-day precision and accuracy of the method were determined. Extending the extraction time at reduced temperature resulted in a significant increase in the recovery of the pharmaceuticals in comparison with traditional extraction methods. The presence of the tested pharmaceuticals at defined retention times was confirmed by mass spectrometry. A recovery procedure for the tested compounds from biological material (medium, cell pellets) was developed at a level ranging between 93 and 99%. The utility of the new HPLC method has been confirmed in drug absorption studies as screening tests for the analysis of the new therapeutic compositions on melanoma cell lines.

Phenanthroindolizidine Alkaloids Isolated from Tylophora ovata as Potent Inhibitors of Inflammation, Spheroid Growth, and Invasion of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC), representing the most aggressive form of breast cancer with currently no targeted therapy available, is characterized by an inflammatory and hypoxic tumor microenvironment. To date, a broad spectrum of anti-tumor activities has been reported for phenanthroindolizidine alkaloids (PAs), however, their mode of action in TNBC remains elusive. Thus, we investigated six naturally occurring PAs extracted from the plant Tylophora ovata: O-methyltylophorinidine (1) and its five derivatives tylophorinidine (2), tylophoridicine E (3), 2-demethoxytylophorine (4), tylophoridicine D (5), and anhydrodehydrotylophorinidine (6). In comparison to natural (1) and for more-in depth studies, we also utilized a sample of synthetic O-methyltylophorinidine (1s). Our results indicate a remarkably effective blockade of nuclear factor kappa B (NFκB) within 2 h for compounds (1) and (1s) (IC50 = 17.1 ± 2.0 nM and 3.3 ± 0.2 nM) that is different from its effect on cell viability within 24 h (IC50 = 13.6 ± 0.4 nM and 4.2 ± 1 nM). Furthermore, NFκB inhibition data for the additional five analogues indicate a structure–activity relationship (SAR). Mechanistically, NFκB is significantly blocked through the stabilization of its inhibitor protein kappa B alpha (IκBα) under normoxic as well as hypoxic conditions. To better mimic the TNBC microenvironment in vitro, we established a 3D co-culture by combining the human TNBC cell line MDA-MB-231 with primary murine cancer-associated fibroblasts (CAF) and type I collagen. Compound (1) demonstrates superiority against the therapeutic gold standard paclitaxel by diminishing spheroid growth by 40% at 100 nM. The anti-proliferative effect of (1s) is distinct from paclitaxel in that it arrests the cell cycle at the G0/G1 state, thereby mediating a time-dependent delay in cell cycle progression. Furthermore, (1s) inhibited invasion of TNBC monoculture spheroids into a matrigel®-based environment at 10 nM. In conclusion, PAs serve as promising agents with presumably multiple target sites to combat inflammatory and hypoxia-driven cancer, such as TNBC, with a different mode of action than the currently applied chemotherapeutic drugs.

Combinatorial effects of melatonin and paclitaxel differ depending on the treatment scheme in colorectal cancer in vitro

AIMS

Colorectal carcinoma (CRC) is the third most prevalent cancer with high mortality. Besides regulating the circadian rhythm, melatonin (MTN) exerts anticancer activities. Paclitaxel (PTX) is successful against different malignancies, however, acquired resistance and variability in patient response restrict its use. mTOR and MAPK pathways are often deregulated in human cancers. We aimed to investigate whether MTN enhances or sensitizes the chemotherapeutic activity of PTX and if so, determine the underlying possible mechanisms in CRC in vitro.

MAIN METHODS

Antiproliferative and cytotoxic activities of PTX and MTN were assessed alone and in combination, as well as with different treatment regimens (renewal or replacement of the treatment after 24 h), up to 48 h. Apoptosis, viability and autophagy were assessed by flow cytometry. mTOR and MAPK pathway activities were investigated by immunoblotting.

KEY FINDINGS

Both drugs reduced cell viability in a dose-dependent manner at 24 and 48 h. Only the highest dose of MTN (500 μM) potentiated the cytotoxicity of PTX (50 nM). Replacement of PTX after 24 h with MTN was superior in reducing cell viability than vice versa via apoptosis induction. Renewal of MTN treatment every 24 h reduced autophagy compared to the control group, while other treatments did not alter the autophagic activity. A 24 h MTN treatment followed by 24 h PTX treatment increased S6 phosphorylation in a mTOR-independent manner and increased Erk1/2 phosphorylation.

SIGNIFICANCE

The present study suggests that sequential treatment with MTN and PTX distinctly affect apoptosis and cytotoxicity via regulating mTOR and MAPK pathways differentially in CRC.

The Proteolytic Landscape of Ovarian Cancer: Applications in Nanomedicine

Ovarian cancer (OvCa) is one of the leading causes of mortality globally with an overall 5-year survival of 47%. The predominant subtype of OvCa is epithelial carcinoma, which can be highly aggressive. This review launches with a summary of the clinical features of OvCa, including staging and current techniques for diagnosis and therapy. Further, the important role of proteases in OvCa progression and dissemination is described. Proteases contribute to tumor angiogenesis, remodeling of extracellular matrix, migration and invasion, major processes in OvCa pathology. Multiple proteases, such as metalloproteinases, trypsin, cathepsin and others, are overexpressed in the tumor tissue. Presence of these catabolic enzymes in OvCa tissue can be exploited for improving early diagnosis and therapeutic options in advanced cases. Nanomedicine, being on the interface of molecular and cellular scales, can be designed to be activated by proteases in the OvCa microenvironment. Various types of protease-enabled nanomedicines are described and the studies that focus on their diagnostic, therapeutic and theranostic potential are reviewed.

Exploring the anticancer activities of novel bioactive compounds derived from endophytic fungi: mechanisms of action, current challenges and future perspectives

Cancer is the second leading cause of death all around the world. The natural compounds derived from the endophytic flora of fungi are possible solutions to cancer treatment because they are safe for health, cost-effective, biocompatible and have fewer toxicity issues. The active ingredients in endophytic fungi that are responsible for anti-cancer activities are alkaloids, terpenoids, glycosides, saponin, peptides, steroids, phenols, quinones, and flavonoids. This review highlights the anti-cancer activities of entophytic fungus against human papillary thyroid carcinoma (IHH4), human pancreatic (PANC-1), ovarian (OVCAR-3), hepatic (HepG2), lung (A-549), human lymphoma (U937), human skin carcinoma (A431), breast (MCF-7), and Kaposi's sarcoma. The emerging evidence suggested that bioactive compounds isolated from endophytic fungi showed their anti-cancer activities by revealing the disturbance of the microtubule network caused by increased levels of Bax and Bcl-2 proteins that triggers cell cycle arrest at the G2-M phase, by inhibiting the DNA replication via binding with topoisomerase II, by regulating the activity of extracellular signal-regulated kinase and NF-kB, by evaluating the levels of p21, p27, and cyclins B/D1/E that led to cell death by apoptosis and cell cycle arrest. This review will assist readers in better comprehending bioactive chemicals and the beneficial interaction between the fungal endophytes and medicinal plants.

Sex Differences in Taxane Toxicities

Simple Summary

Clinically observed sex differences in acute and long-term taxane chemotherapy-induced normal tissue toxicity are routinely documented but remain poorly understood despite the significant impact such toxicities have on treatment tolerance and quality of life outcomes in cancer survivors. This review draws from pre-clinical and clinical literature to highlight sex-specific mechanisms of action in taxane drug toxicity and proposes hypotheses for sex-specific clinical discrepancies in taxane-induced acute and long-term toxicities. To our knowledge, this is the first review exploring how sex as a biological variable impacts taxane-mediated mechanisms of action and clinical outcomes. In doing so, we have provided a novel framework to investigate and understand common sex differences observed in clinical and pre-clinical research.

Abstract

The taxane family of microtubule poisons and chemotherapeutics have been studied for over 50 years and are among the most frequently used antineoplastic agents today. Still, limited research exists characterizing taxane-induced sex-specific mechanisms of action and toxicities in cancer and non-cancerous tissue. Such research is important to advance cancer treatment outcomes as well as to address clinically observed sex-differences in short- and long-term taxane-induced toxicities that have disproportionate effects on female and male cancer patients. To gain more insight into these underlying differences between the sexes, the following review draws from pre-clinical and clinical paclitaxel and taxane oncology literature, examines sex-discrepancies, and highlights uncharacterized sex-dependent mechanisms of action and clinical outcomes. To our knowledge, this is the first literature review to provide a current overview of the basic and clinical sex dimorphisms of taxane-induced effects. Most importantly, we hope to provide a starting point for improving and advancing sex-specific personalized chemotherapy and cancer treatment strategies as well as to present a novel approach to review sex as a biological variable in basic and clinical biology.

Targeting cancer signaling pathways by natural products: Exploring promising anti-cancer agents

Cancer is one of the leading causes of death and significantly burdens the healthcare system. Due to its prevalence, there is undoubtedly an unmet need to discover novel anticancer drugs. The use of natural products as anticancer agents is an acceptable therapeutic approach due to accessibility, applicability, and reduced cytotoxicity. Natural products have been an incomparable source of anticancer drugs in the modern era of drug discovery. Along with their derivatives and analogs, natural products play a major role in cancer treatment by modulating the cancer microenvironment and different signaling pathways. These compounds are effective against several signaling pathways, mainly cell death pathways (apoptosis and autophagy) and embryonic developmental pathways (Notch pathway, Wnt pathway, and Hedgehog pathway). The historical record of natural products is strong, but there is a need to investigate the current role of natural products in the discovery and development of cancer drugs and determine the possibility of natural products being an important source of future therapeutic agents. Many target-specific anticancer drugs failed to provide successful results, which accounts for a need to investigate natural products with multi-target characteristics to achieve better outcomes. The potential of natural products to be promising novel compounds for cancer treatment makes them an important area of research. This review explores the significance of natural products in inhibiting the various signaling pathways that serve as drivers of carcinogenesis and thus pave the way for developing and discovering anticancer drugs.

Silibinin exerts anti-cancer activity on human ovarian cancer cells by increasing apoptosis and inhibiting epithelial-mesenchymal transition (EMT)

BACKGROUND

Silibinin, the principal flavonoid derived from milk thistle seeds, has been demonstrated to have strong inhibitory effects against human malignancies. The inhibitory function of silibinin on ovarian cancer, however, is not fully identified. In this essay, both in vivo and in vitro investigations were conducted to survey the silibinin's blocking effects on ovarian cancer.

METHODS

The impacts of silibinin on two ovarian cancer cell lines, SKOV-3 and A2870, were determined by evaluating cell viability, migration, invasion, and apoptosis. Q-RT-PCR and western blotting techniques were carried out to explore the protein levels of signaling pathway markers. A mouse xenograft model was utilized to determine the silibinin efficacy in inhibiting tumor growth.

RESULTS

After cell treatment with silibinin, cell viability, migration, and invasion were appreciably inhibited in cancer cell lines, but cell apoptosis was promoted. Also, silibinin reversed the epithelial-mesenchymal transition (EMT) mechanism by inducing E-cadherin expression and reducing N-cadherin and vimentin expression, suppressing the levels of regulators related to EMT such as Snail, Slug, and ZEB1 transcription factors, and also decreasing PI3K/AKT, Smad2/3, and β-catenin intermediate molecules in vitro. Silibinin effectively ameliorated tumor growth in vivo.

CONCLUSION

silibinin could be considered a potent agent against ovarian cancer based on the results.

High expression of RIPK2 is associated with Taxol resistance in serous ovarian cancer

Background

Taxol resistance in serous ovarian cancer is responsible for its poor prognosis, yet the underlying mechanism is still poorly understood. Thus, we probed the mechanism of Taxol resistance in serous ovarian cancer with multiple bioinformatic methods to provide novel insights into potential therapies.

Methods

The differentially expressed genes (DEGs) in Taxol-sensitive and Taxol-resistant cell lines and their relationship with the overall survival (OS) and progression-free interval (PFI) of ovarian cancer patients were analyzed using gene expression datasets from the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). The role of receptor interacting serine/threonine kinase 2 (RIPK2) was validated via identification of its coexpressed genes, functional analysis and generation of a protein-protein interaction (PPI) network. The single sample gene set enrichment analysis (ssGSEA) was used to explore immune infiltration, and genomic alterations of RIPK2 were also analyzed via cBio Cancer Genomics Portal (cBioProtal).

Results

RIPK2 was highly expressed in Taxol resistant ovarian cancer cell lines, and its high expression was also linked with shorter OS and PFI in serous ovarian cancer patients. The PPI network analysis and pathway analysis demonstrated that RIPK2 might participate in the positive regulation of NF-κB transcription factor activity. RIPK2 expression was related to tumor microenvironment alterations, which might participate in the formation of Taxol resistance.

Conclusions

Our studies suggested that high expression of RIPK2 is related to Taxol resistance in serous ovarian cancer, and that RIPK2 induces Taxol resistance through NOD1/RIPK2/NF-κB inflammatory pathway activation and tumor microenvironment changes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-022-00986-2.

Exosomes are secreted at similar densities by M21 and PC3 human cancer cells and show paclitaxel solubility

Exosomes are cell-secreted vesicles less than ≈150 nm in size that contain gene-encoding and gene-silencing RNA and cytosolic proteins with roles in intercellular communication. Interest in the use of exosomes as targeted drug delivery vehicles has grown since it was shown that they can bind specific cells and deliver intact genetic material to the cytosol of target cells. We isolated extracellular vesicles (EVs), consisting of a mixture of exosomes and microvesicles, from prostate (PC3) and melanoma (M21) cancer cell lines using serial ultracentrifugation. Interrogation via western blot analysis confirmed enrichment of CD63, a widely recognized EV surface protein, in the EV pellet from both cell lines. Nanoparticle tracking analysis (NTA) of EV pellets revealed that the two cell lines produced distinct vesicle size profiles in the ≈30 nm to ≈400 nm range. NTA further showed that the fraction of exosomes to all EVs was constant, suggesting cellular mechanisms that control the fraction of secreted vesicles that are exosomes. Transmission electron microscopy (TEM) images of the unmodified PC3 EVs showed vesicles with cup-like (i.e., nanocapsule) and previously unreported prolate morphologies. The observed non-spherical morphologies for dehydrated exosomal vesicles (size ≈30-100 nm) are most likely related to the dense packing of proteins in exosome membranes. Solubility phase diagram data showed that EVs enhanced the solubility of paclitaxel (PTX) in aqueous solution compared to a water-only control. Combined with their inherent targeting and cytosol delivery properties, these findings highlight the potential advantages of using exosomes as chemotherapeutic drug carriers in vivo.

Plants in Anticancer Drug Discovery: From Molecular Mechanism to Chemoprevention

Cancer is one of the primary causes of mortality globally, and the discovery of new anticancer drugs is the most important need in recent times. Natural products have been recognized as effective in fight against various diseases including cancer for over 50 years. Plants and microbes are the primary and potential sources of natural compounds to fight against cancer. Moreover, researches in the field of plant-based natural compounds have moved towards advanced and molecular level understandings from the last few decades, leading to the development of potent anticancer agents. Also, plants have been accepted as abundant and prosperous sources for the development of novel therapeutic agents for the management and prevention of different cancer types. The high toxicity of some cancer chemotherapy drugs, as well as their unfavorable side effects and drugs resistance, drives up the demand for natural compounds as new anticancer drugs. In this detailed evidence-based mechanistic review, facts and information about various medicinal plants, their bioactive compounds with their potent anticancer activities against different cancers have been gathered, with further approach to represent the molecular mechanism behind the anticancer activity of these plants. This review will be beneficial for investigators/scientists globally involved in the development of natural, safe, effective, and economical therapeutic agents/drugs against various cancers. This might be an important contribution in the field of drug discovery, where drugs can be used alone or in combination to increase the efficacy of newly synthesized drugs.

Circ_0025033 deficiency suppresses paclitaxel resistance and malignant development of paclitaxel-resistant ovarian cancer cells by modulating the miR-532-3p/FOXM1 network

BACKGROUND

Ovarian cancer (OC) is the main cause of cancer-related death in women, and drug resistance is a leading cause of treatment failure. Recently, the involvement of circular RNAs (circRNAs) in cancer progression has become an area of increased investigation. The objective of this study is to uncover the function and regulatory mechanism of circ_0025033 in paclitaxel (PTX)-resistant OC cells.

METHODS

The expression of circ_0025033, FOXM1 and miR-532-3p was investigated using quantitative real-time polymerase chain reaction (qRT-PCR), and the protein expression of FOXM1 was quantified by western blot. Cell biological functions, including cell viability, migration/invasion and apoptosis, were explored using 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays, transwell assays and flow cytometry assays. The interaction between miR-532-3p and circ_0025033 or FOXM1 predicted by bioinformatics analysis was validated by pull-down assay and dual-luciferase reporter assay. Exosomes were isolated to determine the further function of circ_0025033.

RESULT

Circ_0025033 and FOXM1 were highly expressed, while miR-532-3p was poorly expressed in OC tissues and cells, and the expression pattern was greater in PTX-resistant OC cells. Circ_0025033 knockdown lessened PTX resistance, suppressed migration/invasion and promoted apoptosis of PTX-resistant cells. With respect to mechanism, circ_0025033 upregulated the expression of FOXM1 by targeting miR-532-3p, and circ_0025033 knockdown blocked the malignant activities of PTX-resistant OC cells by enriching miR-532-3p and suppressing FOXM1. Exosomes derived from PTX-resistant cells with circ_0025033 knockdown also could repress the malignant actions of PTX-resistant OC cells.

CONCLUSION

Circ_0025033 downregulation impaired PTX resistance and malignant activities of PTX-resistant OC cells by regulating the miR-532-3p/FOXM1 network.

Degradation of DRAK1 by CUL3/SPOP E3 Ubiquitin ligase promotes tumor growth of paclitaxel-resistant cervical cancer cells

Despite favorable responses to initial chemotherapy, drug resistance is a major cause limiting chemotherapeutic efficacy in many advanced cancers. However, mechanisms that drive drug-specific resistance in chemotherapy for patients with advanced cancers are still unclear. Here, we report a unique role of death-associated protein kinase-related apoptosis-inducing kinase 1 (DRAK1) associated with paclitaxel resistance in cervical cancer cells. Interestingly, DRAK1 protein level was markedly decreased in paclitaxel-resistant cervical cancer cells without affecting its mRNA expression, which resulted in an increase in tumor necrosis factor receptor-associated factor 6 (TRAF6) expression, as well as an activation of TRAF6-mediated nuclear factor-kappa B (NF-κB) signaling cascade, thereby promoting tumor progression. DRAK1 depletion markedly increased the chemotherapeutic IC₅₀ values of paclitaxel in cervical cancer cells. Ectopic expression of DRAK1 inhibited growth of paclitaxel-resistant cervical cancer cells in vitro and in vivo. Furthermore, DRAK1 was markedly underexpressed in chemoresistant cervical cancer patient tissues compared with chemosensitive samples. We found that DRAK1 protein was destabilized through K48-linked polyubiquitination promoted by the Cullin scaffold protein 3 (CUL3) / speckle-type POZ (poxvirus and zinc finger protein) protein (SPOP) E3 ubiquitin ligase in paclitaxel-resistant cells. Collectively, these findings suggest that DRAK1 may serve as a potential predictive biomarker for overcoming paclitaxel resistance in cervical cancer.

Nanoparticles as phytochemical carriers for cancer treatment: News of the last decade

INTRODUCTION

The development and application of novel therapeutic medicines for the treatment of cancer are of vital importance to improve the disease's outcome and survival rate. One noteworthy treatment approach is the use of biologically active compounds present in natural products. Even though these phytocompounds present anti-inflammatory, antioxidant, and anticancer properties, their use is limited essentially due to poor systemic delivery, low bioavailability, and water solubility concerns. To make full use of the anticancer potential of natural products, these limitations need to be technologically addressed. In this sense, nanotechnology emerges as a promising drug delivery system strategy.

AREAS COVERED

In this review, the benefits and potential of nanodelivery systems for natural products encapsulation as promising therapeutic approaches for cancer, which were developed during the last decade, are highlighted.

EXPERT OPINION

The nanotechnology area has been under extensive research in the medical field given its capacity for improving the therapeutic potential of drugs by increasing their bioavailability and allowing a targeted delivery to the tumor site. Thereby, the nanoencapsulation of phytocompounds can have a direct impact on the recognized therapeutic activity of natural products towards cancer.

The potential feasibility of nab-paclitaxel as the first-line chemotherapy for ovarian cancer: clinical development and future perspectives

PURPOSE

Optimal first-line chemotherapy regimens are crucial for epithelial ovarian cancer (EOC) treatment. Nab-paclitaxel has showed its considerable survival and low toxicity profiles in first-line treatment for three solid tumors and is recommended as a treatment for recurrent EOC. We focus on clinical efficacy and safety outcomes of nab-paclitaxel in current clinical studies of EOC treatment and aim to explore the potential feasibility of nab-paclitaxel as the first-line treatment for EOC.

METHODS

We searched for eligible studies up to January 2020 in Pubmed. Outcomes of interests included drug regimes, objective response rate (ORR), median progression free survival (PFS), median overall survival (OS) and main adverse events to determine feasibility of nab-paclitaxel.

RESULTS

This review included nine eligible studies. One study about nab-paclitaxel with carboplatin as first-line therapy in ten cases after hypersensitivity to paclitaxel had an ORR of 100%, median PFS of 16.7 months and median OS of 65.4 months. Evidence of nab-paclitaxel activity in platinum-sensitive EOC demonstrated an ORR of 64%, a median time to response of 1.3 months and PFS of 8.5 months. The ORR, median PFS and median OS range in patients with recurrent platinum-resistant EOC from 23%-72%, 4.0-8.5 months, 16.8-17.4 months, respectively. All studies demonstrated manageable toxicity profile in EOC patients.

CONCLUSION

Nab-paclitaxel presents potentials as the first-line chemotherapy for considerable survival and safety in EOC compared to conventional paclitaxel. However, there is no prospective trial in EOC so far. Therefore, more studies about nab-paclitaxel are needed.

A Network Pharmacology Study to Uncover the Mechanism of FDY003 for Ovarian Cancer Treatment

Ovarian cancer (OC) is one of the deadliest gynecological tumors responsible for 0.21 million deaths per year worldwide. Despite the increasing interest in the use of herbal drugs for cancer treatment, their pharmacological effects in OC treatment are not understood from a systems perspective. Using network pharmacology, we determined the anti-OC potential of FDY003 from a comprehensive systems view. We observed that FDY003 suppressed the viability of human OC cells and further chemosensitized them to cytotoxic chemotherapy. Through network pharmacological and pharmacokinetic approaches, we identified 16 active ingredients in FDY003 and their 108 targets associated with OC mechanisms. Functional enrichment investigation revealed that the targets may coordinate diverse cellular behaviors of OC cells, including their growth, proliferation, survival, death, and cell cycle regulation. Furthermore, the FDY003 targets are important constituents of diverse signaling pathways implicated in OC mechanisms (eg, phosphoinositide 3-kinase [PI3K]-Akt, mitogen-activated protein kinase [MAPK], focal adhesion, hypoxia-inducible factor [HIF]-1, estrogen, tumor necrosis factor [TNF], erythroblastic leukemia viral oncogene homolog [ErbB], Janus kinase [JAK]-signal transducer and activator of transcription [STAT], and p53 signaling). In summary, our data present a comprehensive understanding of the anti-OC effects and mechanisms of action of FDY003.

Emerging uses of PLA-PEG copolymer in cancer drug delivery

Traditional therapies need high systematic dosages that not only destroys cancerous cells but also healthy cells. To overcome this problem recent advancement in nanotechnology specifically in nanomaterials has been extensively done for various biological applications, such as targeted drug delivery. Nanotechnology, as a frontier science, has the potential to break down all the obstacles to be more effective and secure drug delivery system. It is possible to develop nanopolymer based drug carrier that can target drugs with extreme accuracy. Polymers can advance drug delivery technologies by allowing controlled release of therapeutic drugs in stable amounts over long duration of time. For controlled drug delivery, biodegradable synthetic polymers have various benefits over non-biodegradable polymers. Biodegradable polymer either are less toxic or non-toxic. Polylactic Acid (PLA) is one of the most remarkable amphipathic polymers which make it one of the most suitable materials for polymeric micelles. Amphiphilic nanomaterial, such as Polyethylene Glycol (PEG), is one of the most promising carrier for tumor targeting. PLA-PEG as a copolymer has been generally utilized as drug delivery system for the various types of cancer. Chemotherapeutic drugs are stacked into PLA-PEG copolymer and as a result their duration time delays, hence medications arrive at specific tumor site.

A Novel Docetaxel-Biotin Chemical Conjugate for Prostate Cancer Treatment

A novel conjugate of docetaxel and biotin (designated as IDD-1010) was designed and chemically synthesized via an ester linkage at position 2’ carbon in docetaxel. The synthesized pure IDD-1010 exhibits a potent anti-cancer activity in in vitro and in vivo studies. At 10 nM, IDD-1010 has induced increased apoptosis and mitotic arrest of PC3-Luc prostate cancer cells, causing aneuploidy and cell death at higher concentrations. Toxicology studies indicate that the maximal tolerated dose (MTD) of IDD-1010 is 150 mg/kg in mice; equivalent to about 12.2 mg/kg of body weight, or to about an 850 mg dose for a patient weighing 70 kg. The MTD-treated mice exhibited weight gain similar to that of the control group, with no gross pathological signs at 14 days post-dosing. At a lower dose, IDD-1010 treatment did not lead to any significant weight loss in mice, although decreased the tumor volume stemming from injecting cancer cells into the dorsal loop of mouse prostate, and it was found to be more potent than Paclitaxel (reference drug). Similarly, IDD-1010 treatment significantly reduced tumor weight and thereby increased the percentage of mice survival as compared to reference drug-treated and control groups. To summarize, the described experiments using IDD-1010, as compared to the reference drug, strongly suggest a potential treatment utility with a wider therapeutic window for prostate cancer. Henceforth, clinical research on such a novel drug candidate would be greatly worthwhile.

Paclitaxel-Induced Epidermal Alterations: An In Vitro Preclinical Assessment in Primary Keratinocytes and in a 3D Epidermis Model

Paclitaxel is a microtubule-stabilizing chemotherapeutic agent approved for the treatment of ovarian, non-small cell lung, head, neck, and breast cancers. Despite its beneficial effects on cancer and widespread use, paclitaxel also damages healthy tissues, including the skin. However, the mechanisms that drive these skin adverse events are not clearly understood. In the present study, we demonstrated, by using both primary epidermal keratinocytes (NHEK) and a 3D epidermis model, that paclitaxel impairs different cellular processes: paclitaxel increased the release of IL-1α, IL-6, and IL-8 inflammatory cytokines, produced reactive oxygen species (ROS) release and apoptosis, and reduced the endothelial tube formation in the dermal microvascular endothelial cells (HDMEC). Some of the mechanisms driving these adverse skin events in vitro are mediated by the activation of toll-like receptor 4 (TLR-4), which phosphorylate transcription of nuclear factor kappa B (NF-κb). This is the first study analyzing paclitaxel effects on healthy human epidermal cells with an epidermis 3D model, and will help in understanding paclitaxel's effects on the skin.

Current Treatments and New Possible Complementary Therapies for Epithelial Ovarian Cancer

Epithelial ovarian cancer (EOC) is one of the deadliest gynaecological malignancies. The late diagnosis is frequent due to the absence of specific symptomatology and the molecular complexity of the disease, which includes a high angiogenesis potential. The first-line treatment is based on optimal debulking surgery following chemotherapy with platinum/gemcitabine and taxane compounds. During the last years, anti-angiogenic therapy and poly adenosine diphosphate-ribose polymerases (PARP)-inhibitors were introduced in therapeutic schemes. Several studies have shown that these drugs increase the progression-free survival and overall survival of patients with ovarian cancer, but the identification of patients who have the greatest benefits is still under investigation. In the present review, we discuss about the molecular characteristics of the disease, the recent evidence of approved treatments and the new possible complementary approaches, focusing on drug repurposing, non-coding RNAs, and nanomedicine as a new method for drug delivery.

Platinum and Taxane Based Adjuvant and Neoadjuvant Chemotherapy in Early Triple-Negative Breast Cancer: A Narrative Review

Platinum (Pt) derivatives such as cisplatin and carboplatin are the class of drugs with proven activity against triple-negative breast cancer (TNBC). This is due to the ability of Pt compounds to interfere with the DNA repair mechanisms of the neoplastic cells. Taxanes have been efficacious against estrogen receptor-negative tumors and act by disruption of microtubule function. Due to their distinct mechanisms of action and routes of metabolism, the combination of the Pt agents and taxanes results in reduced systemic toxicity, which is ideal for treating TNBC. Also, the sensitivity of BRCA1-mutated cells to taxanes remains unsolved as in vitro evidence indicates resistance against taxanes due to BRCA1 mutations. Recent evidence suggests that the combination of carboplatin and paclitaxel resulted in better pathological complete response (pCR) in patients with TNBC, both in neoadjuvant and adjuvant settings. In vitro studies showed sequential dependency and optimal time scheduling of Pt- and taxane-based chemotherapy. Also, combining carboplatin with docetaxel in the NAC regimen yields an excellent pCR in patients with BRCA-associated and wild-type TNBC. TNBC is a therapeutic challenge that can be tackled by identifying new therapeutic sub-targets and specific cross-sections that can be benefitted from the addition of Pt- and taxane-based chemotherapy. This review summarizes the merits as well as the mechanism of Pt- and taxane-based adjuvant and neoadjuvant chemotherapies in early TNBC from the available and ongoing clinical studies.

Aptamers: an emerging navigation tool of therapeutic agents for targeted cancer therapy

Chemotherapeutic agents have been used for the treatment of numerous cancers, but due to poor selectivity and severe systemic side effects, their clinical application is limited. Single-stranded DNA (ssDNA) or RNA aptamers could conjugate with highly toxic chemotherapy drugs, toxins, therapeutic RNAs or other molecules as novel aptamer-drug conjugates (ApDCs), which are capable of significantly improving the therapeutic efficacy and reducing the systemic toxicity of drugs and have great potential in clinics for targeted cancer therapy. In this review, we have comprehensively discussed and summarized the current advances in the screening approaches of aptamers for specific cancer biomarker targeting and development of the aptamer-drug conjugate strategy for targeted drug delivery. Moreover, considering the huge progress in artificial intelligence (AI) for protein and RNA structure predictions, automatic design of aptamers using deep/machine learning techniques could be a powerful approach for rapid and precise construction of biopharmaceutics (i.e., ApDCs) for application in cancer targeted therapy.

New Trends and Future Opportunities in the Enzymatic Formation of C-C, C-N, and C-O bonds

Organic chemistry provides society with fundamental products we use daily. Concerns about the impact that the chemical industry has over the environment is propelling major changes in the way we manufacture chemicals. Biocatalysis offers an alternative to other synthetic approaches as it employs enzymes, Nature's catalysts, to carry out chemical transformations. Enzymes are biodegradable, come from renewable sources, operate under mild reaction conditions, and display high selectivities in the processes they catalyse. As a highly multidisciplinary field, biocatalysis benefits from advances in different areas, and developments in the fields of molecular biology, bioinformatics, and chemical engineering have accelerated the extension of the range of available transformations (E. L. Bell et al., Nat. Rev. Meth. Prim. 2021, 1, 1-21). Recently, we surveyed advances in the expansion of the scope of biocatalysis via enzyme discovery and protein engineering (J. R. Marshall et al., Tetrahedron 2021, 82, 131926). Herein, we focus on novel enzymes currently available to the broad synthetic community for the construction of new C-C, C-N and C-O bonds, with the purpose of providing the non-specialist with new and alternative tools for chiral and sustainable chemical synthesis.

Unravelling the Anticancer Mechanisms of Traditional Herbal Medicines with Metabolomics

Metabolite profiling of cancer cells presents many opportunities for anticancer drug discovery. The Chinese, Indian, and African flora, in particular, offers a diverse source of anticancer therapeutics as documented in traditional folklores. In-depth scientific information relating to mechanisms of action, quality control, and safety profile will promote their extensive usage in cancer therapy. Metabolomics may be a more holistic strategy to gain valuable insights into the anticancer mechanisms of action of plants but this has remained largely unexplored. This review, therefore, presents the available metabolomics studies on the anticancer effects of herbal medicines commonly used in Africa and Asia. In addition, we present some scientifically understudied ‘candidate plants’ for cancer metabolomics studies and highlight the relevance of metabolomics in addressing other challenges facing the drug development of anticancer herbs. Finally, we discussed the challenges of using metabolomics to uncover the underlying mechanisms of potential anticancer herbs and the progress made in this regard.

Retrospective analysis of Schlafen11 (SLFN11) to predict the outcomes to therapies affecting the DNA damage response

Background

The absence of the putative DNA/RNA helicase Schlafen11 (SLFN11) is thought to cause resistance to DNA-damaging agents (DDAs) and PARP inhibitors.

Methods

We developed and validated a clinically applicable SLFN11 immunohistochemistry assay and retrospectively correlated SLFN11 tumour levels to patient outcome to the standard of care therapies and olaparib maintenance.

Results

High SLFN11 associated with improved prognosis to the first-line treatment with DDAs platinum-plus-etoposide in SCLC patients, but was not strongly linked to paclitaxel–platinum response in ovarian cancer patients. Multivariate analysis of patients with relapsed platinum-sensitive ovarian cancer from the randomised, placebo-controlled Phase II olaparib maintenance Study19 showed SLFN11 tumour levels associated with sensitivity to olaparib. Study19 patients with high SLFN11 had a lower progression-free survival (PFS) hazard ratio compared to patients with low SLFN11, although both groups had the benefit of olaparib over placebo. Whilst caveated by small sample size, this trend was maintained for PFS, but not overall survival, when adjusting for BRCA status across the olaparib and placebo treatment groups, a key driver of PARP inhibitor sensitivity.

Conclusion

We provide clinical evidence supporting the role of SLFN11 as a DDA therapy selection biomarker in SCLC and highlight the need for further clinical investigation into SLFN11 as a PARP inhibitor predictive biomarker.

Paclitaxel: Application in Modern Oncology and Nanomedicine-Based Cancer Therapy

Paclitaxel is a broad-spectrum anticancer compound, which was derived mainly from a medicinal plant, in particular, from the bark of the yew tree Taxus brevifolia Nutt. It is a representative of a class of diterpene taxanes, which are nowadays used as the most common chemotherapeutic agent against many forms of cancer. It possesses scientifically proven anticancer activity against, e.g., ovarian, lung, and breast cancers. The application of this compound is difficult because of limited solubility, recrystalization upon dilution, and cosolvent-induced toxicity. In these cases, nanotechnology and nanoparticles provide certain advantages such as increased drug half-life, lowered toxicity, and specific and selective delivery over free drugs. Nanodrugs possess the capability to buildup in the tissue which might be linked to enhanced permeability and retention as well as enhanced antitumour influence possessing minimal toxicity in normal tissues. This article presents information about paclitaxel, its chemical structure, formulations, mechanism of action, and toxicity. Attention is drawn on nanotechnology, the usefulness of nanoparticles containing paclitaxel, its opportunities, and also future perspective. This review article is aimed at summarizing the current state of continuous pharmaceutical development and employment of nanotechnology in the enhancement of the pharmacokinetic and pharmacodynamic features of paclitaxel as a chemotherapeutic agent.

The FGFR Family Inhibitor AZD4547 Exerts an Antitumor Effect in Ovarian Cancer Cells

The dysregulation of fibroblast growth factor (FGF) signaling has been implicated in tumorigenesis, tumor progression, angiogenesis, and chemoresistance. The small-molecule AZD4547 is a potent inhibitor of FGF receptors. This study was performed to investigate the antitumor effects and determine the mechanistic details of AZD4547 in ovarian cancer cells. AZD4547 markedly inhibited the proliferation and increased the apoptosis of ovarian cancer cells. AZD4547 also suppressed the migration and invasion of ovarian cancer cells under nontoxic conditions. Furthermore, it attenuated the formation of spheroids and the self-renewal capacities of ovarian cancer stem cells and exerted an antiangiogenic effect. It also suppressed in vivo tumor growth in mice. Collectively, this study demonstrated the antitumor effect of AZD4547 in ovarian cancer cells and suggests that it is a promising agent for ovarian cancer therapy.

Clerodane Diterpenoids from an Edible Plant Justicia insularis: Discovery, Cytotoxicity, and Apoptosis Induction in Human Ovarian Cancer Cells

OBJECTIVES

The toxicity of chemotherapeutic anticancer drugs is a serious issue in clinics. Drug discovery from edible and medicinal plants represents a promising approach towards finding safer anticancer therapeutics. Justicia insularis T. Anderson (Acanthaceae) is an edible and medicinal plant in Nigeria. This study aims to discover cytotoxic compounds from this rarely explored J. insularis and investigate their underlying mechanism of action.

METHODS

The cytotoxicity of the plant extract was evaluated in human ovarian cancer cell lines and normal human ovarian surface epithelia (HOE) cells using a sulforhodamine B assay. Bioassay-guided isolation was carried out using column chromatography including HPLC, and the isolated natural products were characterized using GC-MS, LC-HRMS, and 1D/2D NMR techniques. Induction of apoptosis was evaluated using Caspase 3/7, 8, and 9, and Annexin V and PI based flow cytometry assays. SwissADME and SwissTargetPrediction web tools were used to predict the molecular properties and possible protein targets of identified active compounds. Key finding: The two cytotoxic compounds were identified as clerodane diterpenoids: 16(α/β)-hydroxy-cleroda-3,13(14)Z-dien-15,16-olide (1) and 16-oxo-cleroda-3,13(14)E-dien-15-oic acid (2) from the Acanthaceous plant for the first time. Compound 1 was a very abundant compound (0.7% per dry weight of plant material) and was shown to be more potent than compound 2 with IC₅₀ values in the micromolar range against OVCAR-4 and OVCAR-8 cancer cells. Compounds 1 and 2 were less cytotoxic to HOE cell line. Both compounds induced apoptosis by increasing caspase 3/7 activities in a concentration dependent manner. Compound 1 further increased caspase 8 and 9 activities and apoptosis cell populations. Compounds 1 and 2 are both drug like, and compound 1 may target various proteins including a kinase.

CONCLUSIONS

Clerodane diterpenoids (1 and 2) in J. insularis were identified as cytotoxic to ovarian cancer cells via the induction of apoptosis, providing an abundant and valuable source of hit compounds for the treatment of ovarian cancer.

Current Trends and Challenges in Pharmacoeconomic Aspects of Nanocarriers as Drug Delivery Systems for Cancer Treatment

Nanotherapy is a part of nanomedicine that involves nanoparticles as carriers to deliver drugs to target locations. This novel targeting approach has been found to resolve various problems, especially those associated with cancer treatment. In nanotherapy, the carrier plays a crucial role in handling many of the existing challenges, including drug protection before early-stage degradations of active substances, allowing them to reach targeted cells and overcome cell resistance mechanisms. The present review comprises the following sections: the first part presents the introduction of pharmacoeconomics as a branch of healthcare economics, the second part covers various beneficial aspects of the use of nanocarriers for in vitro, in vivo, and pre- and clinical studies, as well as discussion on drug resistance problem and present solutions to overcome it. In the third part, progress in drug manufacturing and optimization of the process of nanoparticle synthesis were discussed. Finally, pharmacokinetic and toxicological properties of nanoformulations due to up-to-date studies were summarized. In this review, the most recent developments in the field of nanotechnology's economic impact, particularly beneficial applications in medicine were presented. Primarily focus on cancer treatment, but also discussion on other fields of application, which are strongly associated with cancer epidemiology and treatment, was made. In addition, the current limitations of nanomedicine and its huge potential to improve and develop the health care system were presented.

Redox-sensitive TRP channels: a promising pharmacological target in chemotherapy-induced peripheral neuropathy

INTRODUCTION

Chemotherapy-induced peripheral neuropathy (CIPN) and its related pain is a major side effect of certain chemotherapeutic agents used in cancer treatment. Available analgesics are mostly symptomatic, and on prolonged treatment, patients become refractive to them. Hence, the development of improved therapeutics that act on novel therapeutic targets is necessary. Potential targets include the redox-sensitive TRP channels [e.g. TRPA1, TRPC5, TRPC6, TRPM2, TRPM8, TRPV1, TRPV2, and TRPV4] which are activated under oxidative stress associated with CIPN.

AREAS COVERED

We have examined numerous neuropathy-inducing cancer chemotherapeutics and their pathophysiological mechanisms. Oxidative stress and its downstream targets, the redox-sensitive TRP channels, together with their potential pharmacological modulators, are discussed. Finally, we reflect upon the barriers to getting new therapeutic approaches into the clinic. The literature search was conducted in PubMed upto and including April 2021.

EXPERT OPINION

Redox-sensitive TRP channels are a promising target in CIPN. Pharmacological modulators of these channels have reduced pain in preclinical models and in clinical studies. Clinical scrutiny suggests that TRPA1, TRPM8, and TRPV1 are the most promising targets because of their pain-relieving potential. In addition to the analgesic effect, TRPV1 agonist-Capsaicin possesses a disease-modifying effect in CIPN through its restorative property in damaged sensory nerves.

CRISPR/Cas9 nanoeditor of double knockout large fragments of E6 and E7 oncogenes for reversing drugs resistance in cervical cancer

Drug resistance of tumor cells is always a headache problem in clinical treatment. In order to combat chemotherapy-resistance in cervical cancer and improve treatment effect, we design a CRISPR/Cas9 nanoeditor to knock out two key oncogenes E6 and E7 that lead to drug tolerance. Meanwhile, the deletion of these two oncogenes can effectively reactivate p53 and pRB signaling pathways that inhibit the growth of tumor cells. Our results demonstrated the nanoeditor could simultaneously delete two oncogenes, and the size of DNA fragments knocked out reaches an unprecedented 563 bp. After the preparation of cationic liposomes combined with chemotherapy drug docetaxel (DOC), this nanosystem can significantly inhibit the drug tolerance of cancer cells and improve the therapeutic effect of cervical cancer. Therefore, this study provides a promising strategy for the treatment of cervical cancer by combining chemotherapy and double-target gene therapy. This strategy can also be applied in other disease models to customize personalized anti-tumor strategies by simply changing chemotherapy drugs and targeted genes.

Induced-damages on preantral follicles by withanolide D, a potent chemotherapy candidate are not attenuated by melatonin

Withanolide D (WD) has been investigated as an antineoplastic drug. This study aimed to evaluate whether melatonin (MT) could attenuate toxic effects on preantral follicles enclosed in the ovarian cortex (experiment 1 - E1) or on isolated secondary follicles (experiment 2 - E2) exposed to WD. For E1, ovarian cortex was incubated for 48 h to: (1) α-MEM⁺; (2) α-MEM⁺ plus 6 μM WD; (3) α-MEM⁺ plus 3 mmol/L MT or (4) α-MEM⁺ plus WD and MT. For E2, secondary follicles were exposed for until 96 h in. (1) only to basic medium (α-MEM⁺⁺/α-MEM⁺⁺); (2) α-MEM⁺⁺ plus 3 mmol/L MT (MT/MT); (3) α-MEM⁺⁺ until 48 h, followed by more 48 h in 6 μM WD (α-MEM⁺⁺/WD) or (4) a pre-exposure to MT for until 48 h, followed by more 48 h of exposure to WD plus MT (MT/MT + WD). The main results obtained showed that exposure to drugs caused damage to follicular morphology (WD or WD + MT) and diameter (WD) in the ovarian cortex or in isolated follicles. In pre-antral follicles in situ, ATM expression increased in the presence of WD, MT or association. As for the secondary follicles, ATM and γH2AX were immunostained in the granulosa and theca cells and oocytes in all treatments. TAp63α was immunostained in follicles included in the ovarian cortex and in isolated follicles. We conclude that melatonin did not provide protection and could have enhanced the toxic effect of WD to follicles surrounded or not by the ovarian cortex.

Reference Module-Based Analysis of Ovarian Cancer Transcriptome Identifies Important Modules and Potential Drugs

Ovarian cancer (OVC) is often diagnosed at the advanced stage resulting in a poor overall outcome for the patient. The disease mechanisms, prognosis, and treatment require imperative elucidation. A rank-based module-centric framework was proposed to analyze the key modules related to the development, prognosis, and treatment of OVC. The ovarian cancer cell line microarray dataset GSE43765 from the Gene Expression Omnibus database was used to construct the reference modules by weighted gene correlation network analysis. Twenty-three reference modules were tested for stability and functionally annotated. Furthermore, to demonstrate the utility of reference modules, two more OVC datasets were collected, and their gene expression profiles were projected to the reference modules to generate a module-level expression. An epithelial-mesenchymal transition module was activated in OVC compared to the normal epithelium, and a pluripotency module was activated in ovarian cancer stroma compared to ovarian cancer epithelium. Seven differentially expressed modules were identified in OVC compared to the normal ovarian epithelium, with five up-regulated, and two down-regulated. One module was identified to be predictive of patient overall survival. Four modules were enriched with SNP signals. Based on differentially expressed modules and hub genes, five candidate drugs were screened. The hub genes of those modules merit further investigation. We firstly propose the reference module-based analysis of OVC. The utility of the analysis framework can be extended to transcriptome data of other kinds of diseases.

Natural Phytochemicals Derived from Gymnosperms in the Prevention and Treatment of Cancers

The incidence of various types of cancer is increasing globally. To reduce the critical side effects of cancer chemotherapy, naturally derived compounds have been considered for cancer treatment. Gymnosperms are a group of plants found worldwide that have traditionally been used for therapeutic applications. Paclitaxel is a commercially available anticancer drug derived from gymnosperms. Other natural compounds with anticancer activities, such as pinostrobin and pinocembrin, are extracted from pine heartwood, and pycnogenol and enzogenol from pine bark. Gymnosperms have great potential for further study for the discovery of new anticancer compounds. This review aims to provide a rational understanding and the latest developments in potential anticancer compounds derived from gymnosperms.

Paclitaxel Nanoparticles Induce Apoptosis and Regulate TXR1, CYP3A4 and CYP2C8 in Breast Cancer and Hepatoma Cells

BACKGROUND AND OBJECTIVE

Although the anticancer potentials of water-insoluble drugs are improved by nanoformulation, other intervening factors may contribute in the drug efficacy. This work was designated to explore the effect of paclitaxel-loaded Poly(Lactic-co-Glycolic Acid) (PLGA) nanoparticles on the viability of cancer cells, the expression of Taxol Resistance gene I (TXR1) and paclitaxel metabolizing genes.

METHODS

Paclitaxel loaded PLGA Nanoparticles (PTX-NPs) were prepared, physically characterized and used in the treatment of breast adenocarcinoma cells (MCF-7) and hepatoma cells (HepG2). Cells viability and apoptosis were investigated. In parallel, RNA was isolated, reverse transcribed and used to monitor the expression levels of TXR1, CYP 3A4 and CYP2C8 genes.

RESULTS

PTX-NPs were characterized by transmission electron microscopy to be of a nano-size sphere-like shape. FTIR analysis revealed good coupling between PTX and PLGA. The encapsulation efficiency was 99% and the drug release demonstrated a progressive releasing phase followed by slower and sustained releasing phases. Although HepG2 cells demonstrated more resistance to PTX than MCF-7 cells, both cell types were more responsive to PTX-NPS compared to PTX. The IC50 values decreased from 19.3 to 6.7 in breast cancer cells and from 42.5 to 13.1μg/ml in hepatoma cells. The apoptosis was the key mechanism in both cells, where at least 44% of cells underwent apoptosis. The expression of TXR1 decreased when either cells were treated with PTX-NPs, respectively, meanwhile the expressions of CYP3A4 and CYP2C8 were increased.

CONCLUSION

Taken together, this in vitro study reports the associations between the enhanced responsiveness of MCF-7 and HepG2 cells to PLGA-loaded paclitaxel nanoparticles and the accompanying decrease in the cells resistance to the PTX and its enhanced metabolism.