Discovery of small molecule cancer drugs: successes, challenges and opportunities

Developing Novel Anticancer Drugs for Targeted Populations: An Update

BACKGROUND

Due to higher failure rates, lengthy time and high cost of the traditional de novo drug discovery and development process, the rate of opportunity to get new, safe and efficacious drugs for the targeted population, including pediatric patients with cancer, becomes sluggish.

OBJECTIVES

This paper discusses the development of novel anticancer drugs focusing on the identification and selection of targeted anticancer drug development for the targeted population.

METHODS

Information presented in this review was obtained from different databases, including PUBMED, SCOPUS, Web of Science, and EMBASE. Various keywords were used as search terms.

RESULTS

The pharmaceutical companies currently are executing drug repurposing as an alternative means to accelerate the drug development process that reduces the risk of failure, time and cost, which take 3-12 years with almost 25% overall probability of success as compared to de novo drug discovery and development process (10- 17 years) which has less than 10% probability of success. An alternative strategy to the traditional de novo drug discovery and development process, called drug repurposing, is also presented.

CONCLUSION

Therefore, to continue with the progress of developing novel anticancer drugs for the targeted population, identification and selection of target to specific disease type is important. Considering the aspects of the age of the patient and the disease stages such as each cancer types are different when we study the disease at a molecular level. Drug repurposing technique becomes an influential alternative strategy to discover and develop novel anticancer drug candidates.

Synthesis and biological evaluation of novel isoxazole-piperazine hybrids as potential anti-cancer agents with inhibitory effect on liver cancer stem cells

In our effort for the development of novel anticancer therapeutics, a series of isoxazole-piperazine analogues were prepared, and primarily screened for their antiproliferative potential against hepatocellular carcinoma (HCC; Huh7/Mahlavu) and breast (MCF-7) cancer cells. All compounds demonstrated potent to moderate cytotoxicity on all cell lines with IC₅₀ values in the range of 0.09-11.7 μM. Further biological studies with 6a and 13d in HCC cells have shown that both compounds induced G1 or G2/M arrests resulting in apoptotic cell death. Subsequent analysis of proteins involved in cell cycle progression as well as proliferation of HCC cells revealed that 6a and 13d may affect cellular survival pathways differently depending on the mutation profiles of cells (p53 and PTEN), epidermal/mesenchymal characteristics, and activation of cell mechanisms through p53 dependent/independent pathways. Lastly, we have demonstrated the potential anti-stemness properties of these compounds in which the proportion of liver CSCs in Huh7 cells (CD133+/EpCAM+) were significantly reduced by 6a and 13d. Furthermore, both compounds caused a significant reduction in expression of stemness markers, NANOG or OCT4 proteins, in Mahlavu and Huh7 cells, as well as resulted in a decreased sphere formation capacity in Huh7 cells. Together, these novel isoxazole-piperazine derivatives may possess potential as leads for development of effective anti-cancer drugs against HCC cells with stem cell-like properties.

MicroRNA-146a limits tumorigenic inflammation in colorectal cancer

Chronic inflammation can drive tumor development. Here, we have identified microRNA-146a (miR-146a) as a major negative regulator of colonic inflammation and associated tumorigenesis by modulating IL-17 responses. MiR-146a-deficient mice are susceptible to both colitis-associated and sporadic colorectal cancer (CRC), presenting with enhanced tumorigenic IL-17 signaling. Within myeloid cells, miR-146a targets RIPK2, a NOD2 signaling intermediate, to limit myeloid cell-derived IL-17-inducing cytokines and restrict colonic IL-17. Accordingly, myeloid-specific miR-146a deletion promotes CRC. Moreover, within intestinal epithelial cells (IECs), miR-146a targets TRAF6, an IL-17R signaling intermediate, to restrict IEC responsiveness to IL-17. MiR-146a within IECs further suppresses CRC by targeting PTGES2, a PGE2 synthesis enzyme. IEC-specific miR-146a deletion therefore promotes CRC. Importantly, preclinical administration of miR-146a mimic, or small molecule inhibition of the miR-146a targets, TRAF6 and RIPK2, ameliorates colonic inflammation and CRC. MiR-146a overexpression or miR-146a target inhibition represent therapeutic approaches that limit pathways converging on tumorigenic IL-17 signaling in CRC.

Optimization binding studies of opioid receptors, saturation and competition, using [3H]-DAMGO

BACKGROUND

Opioid analgesics are prescribed for the moderate to severe pain in the clinic. New analogs of µ-opioid receptors are introduced because they may have less adverse effects and better efficacy. However, these new analogs have to be screened for their receptor affinity before entering clinical trial phases. A common method to do such screening is using radioligand-binding-assay, which is a fast and precise screening technique if the assays are done at an optimum condition. One of the main challenges in this type of screening is to separate free/unbound radioligands from bound radioligands. In this study, we applied a centrifugation method instead of a filtration method to separate free radioligands from bound radioligands, and also optimized the conditions for radioligand receptor binding studies of µ-opioid receptors, saturation, and the competition.

METHODS

We used the midbrain and brainstem of naltrexone-treated rats as a source of µ-opioid receptors, and [³H]-DAMGO as the radioligand. Naloxone was also used to determine non-specific binding. A given amount of membrane protein was incubated with an increasing amount of radioligand at 37 °C to saturate the receptors at equilibrium and the amount of radioligand saturated in the receptors were used in competition studies.

RESULTS

160 µg membrane protein saturated with 20 nM [³H]-DAMGO at 37 °C for 35 min with K_d (15.06 nM, 95% CI 8.117-22.00) and B_max (0.4750 pmol/mg, 95% CI 0.3839-0.5660).

CONCLUSION

Applying the centrifugation method instead of the filtration to separate free from bound radioligand produced repeatable and reliable results. The optimum conditions for radioligand binding were used in competition studies which resulted in the expected outcomes.

The quest to develop an effective therapy for neuroblastoma

Neuroblastoma (NB) is a common solid extracranial tumor developing in pediatric populations. NB can spontaneously regress or grow and metastasize displaying resistance to therapy. This tumor is derived from primitive cells, mainly those of the neural crest, in the sympathetic nervous system and usually develops in the adrenal medulla and paraspinal ganglia. Our understanding of the molecular characteristics of human NBs continues to advance documenting abnormalities at the genome, epigenome, and transcriptome levels. The high-risk tumors have MYCN oncogene amplification, and the MYCN transcriptional regulator encoded by the MYCN oncogene is highly expressed in the neural crest. Studies on the biology of NB has enabled a more precise risk stratification strategy and a concomitant reduction in the required treatment in an expanding number of cases worldwide. However, newer treatment strategies are mandated to improve outcomes in pediatric patients who are at high-risk and display relapse. To improve outcomes and survival rates in such high-risk patients, it is necessary to use a multicomponent therapeutic approach. Accuracy in clinical staging of the disease and assessment of the associated risks based on biological, clinical, surgical, and pathological criteria are of paramount importance for prognosis and to effectively plan therapeutic approaches. This review discusses the staging of NB and the biological and genetic features of the disease and several current therapies including targeted delivery of chemotherapy, novel radiation therapy, and immunotherapy for NB.

Insights and Perspectives Regarding Nanostructured Fluorescent Materials toward Tackling COVID-19 and Future Pandemics

The COVID-19 outbreak has exposed the world's preparation to fight against unknown/unexplored infectious and life-threatening pathogens. The unavailability of vaccines, slow or sometimes unreliable real-time virus/bacteria detection techniques, insufficient personal protective equipment (PPE), and a shortage of ventilators and many other transportation equipments have further raised serious concerns. Material research has been playing a pivotal role in developing antimicrobial agents for water treatment and photodynamic therapy, fast and ultrasensitive biosensors for virus/biomarkers detection, as well as for relevant biomedical and environmental applications. It has been noticed that these research efforts nowadays primarily focus on the nanomaterials-based platforms owing to their simplicity, reliability, and feasibility. In particular, nanostructured fluorescent materials have shown key potential due to their fascinating optical and unique properties at the nanoscale to combat against a COVID-19 kind of pandemic. Keeping these points in mind, this review attempts to give a perspective on the four key fluorescent materials of different families, including carbon dots, metal nanoclusters, aggregation-induced-emission luminogens, and MXenes, which possess great potential for the development of ultrasensitive biosensors and infective antimicrobial agents to fight against various infections/diseases. Particular emphasis has been given to the biomedical and environmental applications that are linked directly or indirectly to the efforts in combating COVID-19 pandemics. This review also aims to raise the awareness of researchers and scientists across the world to utilize such powerful materials in tackling similar pandemics in future.

Discovery of novel triazolophthalazine derivatives as DNA intercalators and topoisomerase II inhibitors

A new series of triazolophthalazine derivatives was designed and synthesized as topoisomerase II (Topo II) inhibitors and DNA intercalators. The synthesized derivatives were evaluated in vitro for their cytotoxic activities against three human cancer cell lines: HepG2, MCF-7, and HCT-116 cells. Compound IX_b was the most potent counterpart with IC₅₀ values of 5.39 ± 0.4, 3.81 ± 0.2, and 4.38 ± 0.3 µM, as it was about 1.47, 1.77, and 1.19 times more active than doxorubicin (IC₅₀  = 7.94 ± 0.6, 6.75 ± 0.4, and 5.23 ± 0.3 µM) against HepG2, MCF-7, and HCT-116 cells, respectively. Additionally, the binding affinity of the synthesized compounds toward the DNA molecule was assessed using the DNA/methyl green assay. Compound IX_b showed an excellent DNA binding affinity with an IC₅₀ value of 27.16 ± 1.2 µM, which was better than that of the reference drug doxorubicin (IC₅₀  = 31.02 ± 1.80 µM). Moreover, compound IX_b was the most potent member among the tested compounds when investigated for their Topo II inhibitory activity. Furthermore, compound IX_b induced apoptosis in HepG2 cells and arrested the cell cycle at the G2/M phase. Additionally, compound IX_b showed Topo II poisoning effects at 2.5 μM and Topo II catalytic inhibitory effects at 5 and 10 μM. Finally, molecular docking studies were carried out against the DNA-Topo II complex and DNA, to investigate the binding patterns of the designed compounds.

Radiolabeled Peptide Probes for Liver Cancer Imaging

Liver cancer/Hepatocellular Carcinoma (HCC) is a leading cause of cancer death and represents an important cause of mortality worldwide. Several biomarkers are overexpressed in liver cancer, such as Glypican 3 (GPC3) and Epidermal Growth Factor Receptor (EGFR). These biomarkers play important roles in the progression of tumors and could serve as imaging and therapeutic targets for this disease. Peptides with adequate stability, receptor binding properties, and biokinetic behavior have been intensively studied for liver cancer imaging. A great variety of them have been radiolabeled with clinically relevant radionuclides for liver cancer diagnosis, and many are promising imaging and therapeutic candidates for clinical translation. Herein, we summarize the advancement of radiolabeled peptides for the targeted imaging of liver cancer.

Therapeutic advances of miRNAs: A preclinical and clinical update

miRNAs, a class of small endogenous RNAs, are one of the essential biopharmaceuticals which are in commercial spans as next-generation medicine in recent times. A snapshot of the current scenario regarding the miRNAs as biopharmaceuticals have been discussed. In this work, biopharmaceutical companies working with miRNAs and the current status of preclinical/clinical trials about miRNA therapeutics have been reviewed. Finally, recent updates on the absorption, distribution, metabolism, and excretion (ADME), as well as a delivery system of miRNAs, have been illustrated.

Long wavelength single photon like driven photolysis via triplet triplet annihilation

Photolysis has enabled the occurrence of numerous discoveries in chemistry, drug discovery and biology. However, there is a dearth of efficient long wavelength light mediated photolysis. Here, we report general and efficient long wavelength single photon method for a wide array of photolytic molecules via triplet-triplet annihilation photolysis. This method is versatile and “LEGO”-like. The light partners (the photosensitizers and the photolytic molecules) can be energetically matched to adapt to an extensive range of electromagnetic spectrum wavelengths and the diversified chemical structures of photoremovable protecting groups, photolabile linkages, as well as a broad array of targeted molecules. Compared to the existing photolysis methods, our strategy of triplet-triplet annihilation photolysis not only exhibits superior reaction yields, but also resolves the photodamage problem, regardless of whether they are single photon or multiple photon associated. Furthermore, the biological promise of this “LEGO” system was illustrated via developing ambient air-stable nanoparticles capable of triplet-triplet annihilation photolysis.

The use of short wavelength light in photolysis applications in chemistry and biology is limited by photolytic reaction yields, photodamage and photobleaching. Here, the authors report a general long wavelength single photon driven photolysis method using a triplet-triplet annihilation process.

New quinoxaline-2(1H)-ones as potential VEGFR-2 inhibitors: design, synthesis, molecular docking, ADMET profile and anti-proliferative evaluations

Eleven new quinoxaline derivatives were designed and synthesized as modified VEGFR-2 inhibitors of our previous work.

Deep neural networks identify signaling mechanisms of ErbB-family drug resistance from a continuous cell morphology space

It is well known that the development of drug resistance in cancer cells can lead to changes in cell morphology. Here, we describe the use of deep neural networks to analyze this relationship, demonstrating that complex cell morphologies can encode states of signaling networks and unravel cellular mechanisms hidden to conventional approaches. We perform high-content screening of 17 cancer cell lines, generating more than 500 billion data points from ∼850 million cells. We analyze these data using a deep learning model, resulting in the identification of a continuous 27-dimension space describing all of the observed cell morphologies. From its morphology alone, we could thus predict whether a cell was resistant to ErbB-family drugs, with an accuracy of 74%, and predict the potential mechanism of resistance, subsequently validating the role of MET and insulin-like growth factor 1 receptor (IGF1R) as drivers of cetuximab resistance in in vitro models of lung and head/neck cancer.

Targeting MYC: From understanding its biology to drug discovery

The MYC oncogene is considered to be a high priority target for clinical intervention in cancer patients due to its aberrant activation in more than 50% of human cancers. Direct small molecule inhibition of MYC has traditionally been hampered by its intrinsically disordered nature and lack of both binding site and enzymatic activity. In recent years, however, a number of strategies for indirectly targeting MYC have emerged, guided by the advent of protein structural information and the growing set of computational tools that can be used to accelerate the hit to lead process in medicinal chemistry. In this review, we provide an overview of small molecules developed for clinical applications of these strategies, which include stabilization of the MYC guanine quadruplex, inhibition of BET factor BRD4, and disruption of the MYC:MAX heterodimer. The recent identification of novel targets for indirect MYC inhibition at the protein level is also discussed.

Drug repurposing using transcriptome sequencing and virtual drug screening in a patient with glioblastoma

Background Precision medicine and drug repurposing are attractive strategies, especially for tumors with worse prognosis. Glioblastoma is a highly malignant brain tumor with limited treatment options and short survival times. We identified novel BRAF (47-438del) and PIK3R1 (G376R) mutations in a glioblastoma patient by RNA-sequencing. Methods The protein expression of BRAF and PIK3R1 as well as the lack of EGFR expression as analyzed by immunohistochemistry corroborated RNA-sequencing data. The expression of additional markers (AKT, SRC, mTOR, NF-κB, Ki-67) emphasized the aggressiveness of the tumor. Then, we screened a chemical library of > 1500 FDA-approved drugs and > 25,000 novel compounds in the ZINC database to find established drugs targeting BRAF47-438del and PIK3R1-G376R mutated proteins. Results Several compounds (including anthracyclines) bound with higher affinities than the control drugs (sorafenib and vemurafenib for BRAF and PI-103 and LY-294,002 for PIK3R1). Subsequent cytotoxicity analyses showed that anthracyclines might be suitable drug candidates. Aclarubicin revealed higher cytotoxicity than both sorafenib and vemurafenib, whereas idarubicin and daunorubicin revealed higher cytotoxicity than LY-294,002. Liposomal formulations of anthracyclines may be suitable to cross the blood brain barrier. Conclusions In conclusion, we identified novel small molecules via a drug repurposing approach that could be effectively used for personalized glioblastoma therapy especially for patients carrying BRAF47-438del and PIK3R1-G376R mutations.

Pharmacological inhibition of hematopoietic progenitor kinase 1 positively regulates T-cell function

Hematopoietic progenitor kinase 1 (HPK1), a hematopoietic cell-specific Ste20-related serine/threonine kinase, is a negative regulator of signal transduction in immune cells, including T cells, B cells, and dendritic cells (DCs). In mice, HPK1 deficiency subverts inhibition of the anti-tumor immune response and is associated with functional augmentation of anti-tumor T cells. We have used a potent, small molecule HPK1 inhibitor, Compound 1, to investigate the effects of pharmacological intervention of HPK1 kinase activity in immune cells. Compound 1 enhanced Th1 cytokine production in T cells and fully reverted immune suppression imposed by the prostaglandin E2 (PGE2) and adenosine pathways in human T cells. Moreover, the combination of Compound 1 with pembrolizumab, a humanized monoclonal antibody against the programmed cell death protein 1 (PD-1), demonstrated a synergistic effect, resulting in enhanced interferon (IFN)-γ production. Collectively, our results suggest that blocking HPK1 kinase activity with small molecule inhibitors alone or in combination with checkpoint blockade may be an attractive approach for the immunotherapy of cancer.

Recognizing and stabilizing miR-21 by chiral ruthenium(II) complexes

MiR-21, a non-coding miRNA with 22 nucleotides, plays an important part in the proliferation, invasion, and metastasis of tumor cells. The present study demonstrates that isomers of chiral ruthenium(II) complexes with alkynes (Λ-1 and Δ-1) were synthesized by Songogashira coupling reaction by using microwave-assisted synthetic technology. The isomers can recognize and stabilize miR-21, with the Λ-isomer showing a stronger binding capacity than the Δ-isomer. Further studies showed that both isomers can be uptaken by MDA-MB-231 cells and enriched in the nucleus. Treatment with the Λ-/Δ-isomer downregulated the expression of miR-21. In a word, the development of chiral ruthenium(II) complexes act as potential inhibitors against tumor cells by recognizing, stabilizing, and regulating the expression of miR-21.

Inhibition of poly(ADP-ribose) polymerase induces synthetic lethality in BRIP1 deficient ovarian epithelial cells

OBJECTIVE

Pathogenic variations in the homologous recombination (HR) gene, BRCA1 interacting protein C-terminal helicase 1 (BRIP1) increase the risk for ovarian cancer. PARP inhibitors (PARPi) exert a synthetic lethal effect in BRCA-mutated ovarian cancers. Effective HR requires cooperation between BRCA1 and BRIP1; therefore, BRIP1-incompetancy may predict vulnerability to synthetic lethality. Here we investigated the response of ovarian epithelial cells with defective BRIP1 function to PARPi, and compared these cells to those lacking BRCA1 activity.

METHODS

We engineered Chinese Hamster ovarian (CHO) epithelial cells to express deficient BRIP1 or BRCA1, and exposed them to olaparib with or without carboplatin or cisplatin. We assessed cellular proliferation and survival; we calculated inhibitory concentrations and combination and reduction drug indices.

RESULTS

BRIP1 and BRCA1 inactivation impedes HR activity, decreases cellular proliferation and compromises DNA damage recovery. Platinum agent exposure impairs cellular survival. Olaparib exposure alone decreases cell viability in BRCA1-deficient cells, although has no effect on BRIP1-deficient cells. Combining carboplatin or cisplatin with olaparib synergistically attenuates cellular survival, consistent with synthetic lethality.

CONCLUSIONS

BRIP1-deficient ovarian epithelial cells exhibit defective HR, resulting in synthetic lethality when exposed to a platinum agent/PARPi combination. PARPi alone had no effect; this lack of effect may result from distinguishing molecular properties of BRIP1and/or consequences of genomic background. Our study identifies altered BRIP1 as a target for precision medicine-based therapies for ovarian cancers. This investigation supports consideration of the use of a platinum agent/PARPi combination in ovarian cancers depending upon genetic profile and genomic background.

Recent advances on synthesis and biological activities of aurones

Aurones are naturally occurring structural isomerides of flavones that have diverse bioactivities including antiviral, antibacterial, antifungal, anti-inflammatory, antitumor, antimalarial, antioxidant, neuropharmacological activities and so on. They constitute an important class of pharmacologically active scaffolds that exhibit multiple biological activities via diverse mechanisms. This review article provides an update on the recent advances (2013-2020.4) in the synthesis and biological activities of these derivatives. In the cases where sufficient information is available, some important structure-activity relationships (SAR) of their biological activities were presented, and on the strength of our expertise in medicinal chemistry and careful analysis of the recent literature, for the potential of aurones as medicinal drugs is proposed.

Is highly expressed ACE 2 in pregnant women "a curse" in times of COVID-19 pandemic?

Angiotensin-converting enzyme 2 (ACE 2) is a membrane-bound enzyme that cleaves angiotensin II (Ang II) into angiotensin (1-7). It also serves as an important binding site for SARS-CoV-2, thereby, facilitating viral entry into target host cells. ACE 2 is abundantly present in the intestine, kidney, heart, lungs, and fetal tissues. Fetal ACE 2 is involved in myocardium growth, lungs and brain development. ACE 2 is highly expressed in pregnant women to compensate preeclampsia by modulating angiotensin (1-7) which binds to the Mas receptor, having vasodilator action and maintain fluid homeostasis. There are reports available on Zika, H1N1 and SARS-CoV where these viruses have shown to produce fetal defects but very little is known about SARS-CoV-2 involvement in pregnancy, but it might have the potential to interact with fetal ACE 2 and enhance COVID-19 transmission to the fetus, leading to fetal morbidity and mortality. This review sheds light on a path of SARS-CoV-2 transmission risk in pregnancy and its possible link with fetal ACE 2.

Determination of lumefantrine as an effective drug against Toxoplasma gondii infection - in vitro and in vivo study

Toxoplasma gondii is an obligate intracellular protozoan parasite, which can infect almost all warm-blooded animals, including humans, leading to toxoplasmosis. Currently, the effective treatment for human toxoplasmosis is the combination of sulphadiazine and pyrimethamine. However, both drugs have serious side-effects and toxicity in the host. Therefore, there is an urgent need for the discovery of new anti-T. gondii drugs with high potency and less or no side-effects. Our findings suggest that lumefantrine exerts activity against T. gondii by inhibiting its proliferation in Vero cells in vitro without being toxic to Vero cells (P ≤ 0.01). Lumefantrine prolonged mice infected with T. gondii from death for 3 days at the concentration of 50 μg L⁻¹ than negative control (phosphate-buffered saline treated only), and reduced the parasite burden in mouse tissues in vivo (P ≤ 0.01; P ≤ 0.05). In addition, a significant increase in interferon gamma (IFN-γ) production was observed in high-dose lumefantrine-treated mice (P ≤ 0.01), whereas interleukin 10 (IL-10) and IL-4 levels increased in low-dose lumefantrine-treated mice (P ≤ 0.01). The results demonstrated that lumefantrine may be a promising agent to treat toxoplasmosis, and more experiments on the protective mechanism of lumefantrine should be undertaken in further studies.

A Small-Molecule Inhibitor to the Cytokine Interleukin-4

Interleukin-4 (IL-4) is a multifunctional cytokine and an important regulator of inflammation. When deregulated, IL-4 activity is associated with asthma, allergic inflammation, and multiple types of cancer. While antibody-based inhibitors targeting the soluble cytokine have been evaluated clinically, they failed to achieve their end points in trials. Small-molecule inhibitors are an attractive alternative, but identifying effective chemotypes that inhibit the protein-protein interactions between cytokines and their receptors remains an active area of research. As a result, no small-molecule inhibitors to the soluble IL-4 cytokine have yet been reported. Here, we describe the first IL-4 small-molecule inhibitor identified and characterized through a combination of binding-based approaches and cell-based activity assays. The compound features a nicotinonitrile scaffold with micromolar affinity and potency for the cytokine and disrupts type II IL-4 signaling in cells. Small-molecule inhibitors of these important cell-signaling proteins have implications for numerous immune-related disorders and inform future drug discovery and design efforts for these challenging protein targets.

Chemical Biology Toolkit for DCLK1 Reveals Connection to RNA Processing

Doublecortin-like kinase 1 (DCLK1) is critical for neurogenesis, but overexpression is also observed in multiple cancers and is associated with poor prognosis. Nevertheless, the function of DCLK1 in cancer, especially the context-dependent functions, are poorly understood. We present a "toolkit" that includes the DCLK1 inhibitor DCLK1-IN-1, a complementary DCLK1-IN-1-resistant mutation G532A, and kinase dead mutants D511N and D533N, which can be used to investigate signaling pathways regulated by DCLK1. Using a cancer cell line engineered to be DCLK1 dependent for growth and cell migration, we show that this toolkit can be used to discover associations between DCLK1 kinase activity and biological processes. In particular, we show an association between DCLK1 and RNA processing, including the identification of CDK11 as a potential substrate of DCLK1 using phosphoproteomics.

The Anti-Tumor Effects of Oenothera odorata Extract Are Mediated by Inhibition of Glycolysis and Cellular Respiration in Cancer Cells

Cancer is caused by uncontrolled cell division and is a leading cause of mortality worldwide. Oenothera odorata (O. odorata) extract is used in herbal medicine to inhibit inflammation, but its potential anti-tumor properties have not been fully evaluated. Here, we demonstrated that O. odorata extract inhibits the proliferation of lung adenocarcinoma and melanoma cell lines In Vitro, and also inhibits the growth of melanoma cells In Vivo. After partitioning the extract with n-hexane, chloroform, ethyl acetate, and n-butanol, it was found that the butanol-soluble (OOB) and water-soluble (OOW) fractions of O. odorata extract are effective at inhibiting tumor cell growth In Vivo although OOW is more effective than OOB. Interestingly, these fractions did not inhibit the growth of non-cancerous cells. The anti-proliferative effects of the OOW fraction were found to be mediated by inhibition of glycolysis and cellular respiration. UPLC of both fractions showed two major common peaks, which were predicted to be hydrolyzable tannin-related compounds. Taken together, these data suggest that O. odorata extract has anti-tumor properties, and the molecular mechanism involves metabolic alterations and inhibition of cell proliferation. O. odorata extract therefore holds promise as a novel natural product for the treatment of cancer.

Promoting Dual-Targeting Anticancer Effect by Regulating the Dynamic Intracellular Self-Assembly

Despite the promise of nanomedicine in the fight against complex diseases, the enthusiasm for its pharmaceutical development is backed by the elevated costs associated with the R&D process. Therefore, as a compromise solution, nanotechnology was mainly applied as a drug delivery system to improve bioavailability and controllability of pharmaceutical drugs. Attempting to break the restrictions without elevating potential costs, we multiply the functions of excipients in the nanodelivery system by endowing subcellular-targeting ability. To prove the concept, fluorescent endoplasmic reticulum-targeted short peptides were covalently connected to chemotherapy medication chlorambucil achieving enhanced drug-loading efficiency. Via visualized intracellular dynamic enzyme-catalyzed hydrolysis, the ER-targeting excipient and nucleus-targeting chlorambucil are released simultaneously, achieving a synergistic anticancer effect and elucidating the influence of intracellular self-assembly transition on enzymatic reactions.

iGMDR: Integrated Pharmacogenetic Resource Guide to Cancer Therapy and Research

Current pharmacogenetic studies have obtained many genetic models that can predict the therapeutic efficacy of anticancer drugs. Although some of these models are of crucial importance and have been used in clinical practice, these very valuable models have not been well adopted into cancer research to promote the development of cancer therapies due to the lack of integration and standards for the existing data of the pharmacogenetic studies. For this purpose, we built a resource investigating genetic model of drug response (iGMDR), which integrates the models from in vitro and in vivo pharmacogenetic studies with different omics data from a variety of technical systems. In this study, we introduced a standardized process for all integrations, and described how users can utilize these models to gain insights into cancer. iGMDR is freely accessible at https://igmdr.modellab.cn.

Cranial Neural Crest Cells and Their Role in the Pathogenesis of Craniofacial Anomalies and Coronal Craniosynostosis

Craniofacial anomalies are among the most common of birth defects. The pathogenesis of craniofacial anomalies frequently involves defects in the migration, proliferation, and fate of neural crest cells destined for the craniofacial skeleton. Genetic mutations causing deficient cranial neural crest migration and proliferation can result in Treacher Collins syndrome, Pierre Robin sequence, and cleft palate. Defects in post-migratory neural crest cells can result in pre- or post-ossification defects in the developing craniofacial skeleton and craniosynostosis (premature fusion of cranial bones/cranial sutures). The coronal suture is the most frequently fused suture in craniosynostosis syndromes. It exists as a biological boundary between the neural crest-derived frontal bone and paraxial mesoderm-derived parietal bone. The objective of this review is to frame our current understanding of neural crest cells in craniofacial development, craniofacial anomalies, and the pathogenesis of coronal craniosynostosis. We will also discuss novel approaches for advancing our knowledge and developing prevention and/or treatment strategies for craniofacial tissue regeneration and craniosynostosis.

Inhibition of PI3K/mTOR Pathways with GDC-0980 in Pediatric Leukemia: Impact on Abnormal FLT-3 Activity and Cooperation with Intracellular Signaling Targets

BACKGROUND

GDC-0980 is a selective small molecule inhibitor of class I PI3K and mTOR pathway with a potent anti-proliferative activity.

OBJECTIVE

We set out to evaluate the efficacy of GDC-0980, in pre-clinical studies, against pediatric leukemia cells.

METHODS

The anti-neoplastic activity of GDC-0980 was evaluated in vitro using five different pediatric leukemia cells.

RESULTS

Our data show that GDC-0980 significantly inhibited the proliferation of leukemia cell lines, KOPN8 (IC50, 532 nM), SEM (IC50,720 nM), MOLM-13 (IC50,346 nM), MV4;11 (IC50,199 nM), and TIB-202 (IC50, 848 nM), compared to normal control cells (1.23 µM). This antiproliferative activity was associated with activation of cellular apoptotic mechanism characterized by a decrease in Bcl-2 protein phosphorylation and enhanced PARP cleavage. Western blot analyses of GDC-0980 treated cells also showed decreased phosphorylation levels of mTOR, Akt and S6, but not ERK1/2. Notably, FLT3 phosphorylation was decreased in Molm-13 and MV4;11 cells following the application of GDC-0980. We further examined cellular viability of GDC-0980-treated primary leukemia cells isolated from pediatric leukemia patients. This study revealed a potential therapeutic effect of GDC-0980 on two ALL patients (IC50's, 1.23 and 0.625 µM, respectively). Drug combination analyses of GDC-0980 demonstrated a synergistic activity with the MEK inhibitor Cobimetinib (MV4-11; 11, CI, 0.25, SEM, CI, 0.32, and TIB-202, CI, 0.55) and the targeted FLT3 inhibitor, Crenolanib (MV4-11; 11, CI, 0.25, SEM, CI, 0.7, and TIB-202, CI, 0.42).

CONCLUSION

These findings provide initial proof-of-concept data and rationale for further investigation of GDC-0980 in selected subgroups of pediatric leukemia patients.

Ultrasensitive Detection of Enzymatic Activity Using Single Molecule Arrays

Enzyme assays are important for many applications including clinical diagnostics, functional proteomics, and drug discovery. Current methods for enzymatic activity measurement often suffer from low analytical sensitivity. We developed an ultrasensitive method for the detection of enzymatic activity using Single Molecule Arrays (eSimoa). The eSimoa assay is accomplished by conjugating substrates to paramagnetic beads and measuring the conversion of substrates to products using single molecule analysis. We demonstrated the eSimoa method for the detection of protein kinases, telomerase, histone H3 methyltransferase SET7/9, and polypeptide N-acetylgalactosaminyltransferase with unprecedented sensitivity. In addition, we tested enzyme inhibition and performed theoretical calculations for the binding of inhibitor to its target enzyme and show the need for an ultrasensitive enzymatic assay to evaluate the potency of tight binding inhibitors. The eSimoa assay was successfully used to determine inhibition constants of both bosutinib and dasatinib. Due to the ultrasensitivity of this method, we also were able to measure the kinase activities at the single cell level. We show that the eSimoa assay is a simple, fast, and highly sensitive approach, which can be easily extended to detect a variety of other enzymes, providing a promising platform for enzyme-related fundamental research and inhibitor screening.

Thermodynamic Dissection of the Intercalation Binding Process of Doxorubicin to dsDNA with Implications of Ionic and Solvent Effects

Doxorubicin (DOX) is a cancer drug that binds to dsDNA through intercalation. A comprehensive microsecond timescale molecular dynamics study is performed for DOX with 16 tetradecamer dsDNA sequences in explicit aqueous solvent, in order to investigate the intercalation process at both binding stages (conformational change and insertion binding stages). The molecular mechanics generalized Born surface area (MM-GBSA) method is adapted to quantify and break down the binding free energy (BFE) into its thermodynamic components, for a variety of different solution conditions as well as different DNA sequences. Our results show that the van der Waals interaction provides the largest contribution to the BFE at each stage of binding. The sequence selectivity depends mainly on the base pairs located downstream from the DOX intercalation site, with a preference for (AT)₂ or (TA)₂ driven by the favorable electrostatic and/or van der Waals interactions. Invoking the quartet sequence model proved to be most successful to predict the sequence selectivity. Our findings also indicate that the aqueous bathing solution (i.e., water and ions) opposes the formation of the DOX-DNA complex at every binding stage, thus implying that the complexation process preferably occurs at low ionic strength and is crucially dependent on solvent effects.

Novel Therapeutic Approaches of Ion Channels and Transporters in Cancer

The expression and function of many ion channels and transporters in cancer cells display major differences in comparison to those from healthy cells. These differences provide the cancer cells with advantages for tumor development. Accordingly, targeting ion channels and transporters have beneficial anticancer effects including inhibition of cancer cell proliferation, migration, invasion, metastasis, tumor vascularization, and chemotherapy resistance, as well as promoting apoptosis. Some of the molecular mechanisms associating ion channels and transporters with cancer include the participation of oxidative stress, immune response, metabolic pathways, drug synergism, as well as noncanonical functions of ion channels. This diversity of mechanisms offers an exciting possibility to suggest novel and more effective therapeutic approaches to fight cancer. Here, we review and discuss most of the current knowledge suggesting novel therapeutic approaches for cancer therapy targeting ion channels and transporters. The role and regulation of ion channels and transporters in cancer provide a plethora of exceptional opportunities in drug design, as well as novel and promising therapeutic approaches that may be used for the benefit of cancer patients.

Mechanisms of Action for Small Molecules Revealed by Structural Biology in Drug Discovery

Small-molecule drugs are organic compounds affecting molecular pathways by targeting important proteins. These compounds have a low molecular weight, making them penetrate cells easily. Small-molecule drugs can be developed from leads derived from rational drug design or isolated from natural resources. A target-based drug discovery project usually includes target identification, target validation, hit identification, hit to lead and lead optimization. Understanding molecular interactions between small molecules and their targets is critical in drug discovery. Although many biophysical and biochemical methods are able to elucidate molecular interactions of small molecules with their targets, structural biology is the most powerful tool to determine the mechanisms of action for both targets and the developed compounds. Herein, we reviewed the application of structural biology to investigate binding modes of orthosteric and allosteric inhibitors. It is exemplified that structural biology provides a clear view of the binding modes of protease inhibitors and phosphatase inhibitors. We also demonstrate that structural biology provides insights into the function of a target and identifies a druggable site for rational drug design.

Human intratumoral therapy: Linking drug properties and tumor transport of drugs in clinical trials

Cancer therapies aim to kill tumor cells directly or engage the immune system to fight malignancy. Checkpoint inhibitors, oncolytic viruses, cell-based immunotherapies, cytokines, and adjuvants have been applied to prompt the immune system to recognize and attack cancer cells. However, systemic exposure of cancer therapies can induce unwanted adverse events. Intratumoral administration of potent therapies utilizes small amounts of drugs, in an effort to minimize systemic exposure and off-target toxicities. Here, we discuss the properties of the tumor microenvironment and transport considerations for intratumoral drug delivery. Specifically, we consider various tumor tissue factors and physicochemical factors that can affect tumor retention after intratumoral injection. We also review approved and clinical-stage intratumoral therapies and consider how the molecular and biophysical properties (e.g. size and charge) of these therapies influences intratumoral transport (e.g. tumor retention and cellular uptake). Finally, we offer a critical review and highlight several emerging approaches to promote tumor retention and limit systemic exposure of potent intratumoral therapies.

Syringic acid modulates molecular marker-involved cell proliferation, survival, apoptosis, inflammation, and angiogenesis in DMBA-induced oral squamous cell carcinoma in Syrian hamsters

Despite, different medicinal phyto compounds giving an inexhaustible variety of anticancer drugs, potent signalling mechanism of leads  the key successes of anticancer agent, anti-inflammatory, induction of apoptosis, and antiangiogenic. The current study was conducted to estimate the effect of syringic acid (SA) on tumor necrosis factor-α (TNF-α)-mediated nuclear factor-κB (NF-κB) signaling pathways, inducing apoptosis and angiogenic signaling pathways in a hamster model by preneoplastic stages, histological, immunohistochemistry and immunoblots analysis. Hamsters were given oral cancer by painting 0.5% 7,12-dimethylbenz[a]anthracene (DMBA) for 10 weeks. The DMBA-painted hamsters were treated with an effective dose (50 mg/kg body weight) of SA for 14 weeks. The results revealed that oral preadministration of SA to DMBA-treated hamster oral tumorigenesis significantly increased Bcl-2-associated X protein, caspases-3 and -9, and reduced B-cell lymphoma protein 2 and inflammatory cyclooxygenase-2 (COX-2), inducible nitric oxide synthase, and TNF-α expression through NF-κB, and angiogenic vascular endothelial growth factor markers. Taken together, the current study suggests that SA prevents the DMBA-induced hamster buccal pouch carcinogenesis by triggering intrinsic apoptotic pathway via abrogation of the downstream signaling molecules such as COX-2, NF-κB, and TNF-α. This type of preventive strategy based on animal study will offer a means to design chemoprevention trials for humans.

Structure-based screening of novel lichen compounds against SARS Coronavirus main protease (Mpro) as potentials inhibitors of COVID-19

The outbreak of SARS-CoV-2 and deaths caused by it all over the world have imposed great concern on the scientific community to develop potential drugs to combat Coronavirus disease-19 (COVID-19). In this regard, lichen metabolites may offer a vast reservoir for the discovery of antiviral drug candidates. Therefore, to find novel compounds against COVID-19, we created a library of 412 lichen compounds and subjected to virtual screening against the SARS-CoV-2 Main protease (Mpro). All the ligands were virtually screened, and 27 compounds were found to have high affinity with Mpro. These compounds were assessed for drug-likeness analysis where two compounds were found to fit well for redocking studies. Molecular docking, drug-likeness, X-Score, and toxicity analysis resulting in two lichen compounds, Calycin and Rhizocarpic acid with Mpro-inhibiting activity. These compounds were finally subjected to molecular dynamics simulation to compare the dynamics behavior and stability of the Mpro after ligand binding. The binding energy was calculated by MM-PBSA method to determine the intermolecular protein-ligand interactions. Our results showed that two compounds; Calycin and Rhizocarpic acid had the binding free energy of - 42.42 kJ mol/1 and - 57.85 kJ mol/1 respectively as compared to reference X77 (- 91.78 kJ mol/1). We concluded that Calycin and Rhizocarpic acid show considerable structural and pharmacological properties and they can be used as hit compounds to develop potential antiviral agents against SARS-CoV-2. These lichen compounds may be a suitable candidate for further experimental analysis.

The small molecule antibody mimic SH7139 targets a family of HLA-DRs expressed by B-cell lymphomas and other solid cancers

Selective high-affinity ligands (SHALs) belong to a novel class of small-molecule cancer therapeutics that function as targeted prodrugs. SH7139, the most advanced of the SHAL drugs designed to bind to a unique β-subunit structural epitope located on HLA-DR10, has exhibited exceptional preclinical efficacy and safety profiles. A comparison of SH7139 and SH7129, a biotin derivative of the drug developed for use as a diagnostic, showed the incorporation of a biotin tag did not alter the SHALs ability to target or kill HLA-DR10 expressing Raji cells. The use of SH7129 in an immuno-histochemical type assay to stain peripheral blood mononuclear cells (PBMCs) obtained from individuals expressing specific HLA-DRB1 alleles has also revealed that in addition to HLA-DR10, seven other more commonly expressed HLA-DRs are targeted by the drug. Computational dockings of the SHAL's recognition ligands to a number of HLA-DR structures explain, in part, why the targeting domains of SH7129 and SH7139 bind to some HLA-DRs but not others. The results also substantiate the selectivity of SH7129 and suggest it may prove useful as a companion diagnostic for pre-screening biopsy samples to identify those patients whose tumours should respond to SH7139 therapy.

Pyrazolone ligation-mediated versatile sequential bioconjugations

Bioconjugation chemistries are critical tools in biotherapeutics discovery. The past efforts have been exclusively focused on two-segment conjugations. However, emerging research directions, such as polypharmacy biotherapeutics, desire multiple-component bioconjugations where more than two pharmacologically related biomolecules can be assembled into a single construct in high efficiency. We present here a set of sequential bioconjugation chemistries centered on a pyrazolone structural motif. It starts with a clickable “pyrazolone ligation” between a hydrazine group and a β-ketoester moiety followed by the conjugation between the newly formed pyrazolone core and an aldehyde-bearing biomolecule through a Knoevenagel reaction forming a Michael addition acceptor that can effectively capture a thiol-bearing biomolecule. When utilized intermolecularly, it quickly assembles four segments together forming a quadruple functional construct. When applied intramolecularly, it offers a set of highly diverse biomolecule scaffolds including stapled peptides and poly-macrocyclic peptides. We envision broad utilities of such sequential ligation chemistries.

A multiple component sequential bioconjugation chemistry establishes upon the joined force of hydrazine, β-keto ester, thiol and aldehyde.

ASR488, a novel small molecule, activates an mRNA binding protein, CPEB1, and inhibits the growth of bladder cancer

Due to a lack of mechanistic insights, muscle-invasive bladder cancer (MIBC) remains incurable and is one of the most lethal types of cancer in the United States. The present study investigated changes in the molecular signatures of MIBC cells (TCCSUP and HT1376) after treatment with a novel small molecule, ASR488, to gain knowledge of the mechanisms that inhibited MIBC cell growth. ASR488 treatment initiated apoptotic signaling in MIBC cells. Pathway enrichment analysis was used to analyze the changes in function of differentially expressed genes. Gene Ontology analysis, as well as Kyoto Encyclopedia of Genes and Genomes analysis, was also performed. These analyses along with reactome pathway enrichment analyses indicated that the genes upregulated in the ASR488-treated cells are involved in focal adhesion, neurotrophin signaling, p53 signaling, endoplasmic reticulum functioning in terms of protein processing, and pathways related to bladder cancer. The genes downregulated in ASR488-treated MIBC cells were mainly involved in DNA replication, mismatch repair, RNA degradation, nucleotide excision repair and TGFβ signaling (P<0.05). Furthermore, reverse transcription-quantitative PCR analysis revealed an increase in transcripts of the most upregulated genes in ASR 488-treated MIBC cells: CPEB1 (36-fold), IL11 (30-fold), SFN (20.12-fold) and CYP4F11 (15.8-fold). In conclusion, the analysis of biological functions of the most differentially expressed genes revealed possible mechanisms that may be associated with the aggressiveness of MIBC.

Small Molecule Inhibitors Targeting Gαi2 Protein Attenuate Migration of Cancer Cells

Heterotrimeric G-proteins are ubiquitously expressed in several cancers, and they transduce signals from activated G-protein coupled receptors. These proteins have numerous biological functions, and they are becoming interesting target molecules in cancer therapy. Previously, we have shown that heterotrimeric G-protein subunit alphai2 (Gαi2) has an essential role in the migration and invasion of prostate cancer cells. Using a structure-based approach, we have synthesized optimized small molecule inhibitors that are able to prevent specifically the activation of the Gαi2 subunit, keeping the protein in its inactive GDP-bound state. We observed that two of the compounds (13 and 14) at 10 μΜ significantly inhibited the migratory behavior of the PC3 and DU145 prostate cancer cell lines. Additionally, compound 14 at 10 μΜ blocked the activation of Gαi2 in oxytocin-stimulated prostate cancer PC3 cells, and inhibited the migratory capability of DU145 cells overexpressing the constitutively active form of Gαi2, under basal and EGF-stimulated conditions. We also observed that the knockdown or inhibition of Gαi2 negatively regulated migration of renal and ovarian cancer cell lines. Our results suggest that small molecule inhibitors of Gαi2 have potential as leads for discovering novel anti-metastatic agents for attenuating the capability of cancer cells to spread and invade to distant sites.

Next-Generation Sequencing: An Emerging Tool for Drug Designing

BACKGROUND

With the outbreak of high throughput next-generation sequencing (NGS), the biological research of drug discovery has been directed towards the oncology and infectious disease therapeutic areas, with extensive use in biopharmaceutical development and vaccine production.

METHOD

In this review, an effort was made to address the basic background of NGS technologies, potential applications of NGS in drug designing. Our purpose is also to provide a brief introduction of various Nextgeneration sequencing techniques.

DISCUSSIONS

The high-throughput methods execute Large-scale Unbiased Sequencing (LUS) which comprises of Massively Parallel Sequencing (MPS) or NGS technologies. The Next geneinvolved necessarily executes Largescale Unbiased Sequencing (LUS) which comprises of MPS or NGS technologies. These are related terms that describe a DNA sequencing technology which has revolutionized genomic research. Using NGS, an entire human genome can be sequenced within a single day.

CONCLUSION

Analysis of NGS data unravels important clues in the quest for the treatment of various lifethreatening diseases and other related scientific problems related to human welfare.

Monitoring cell endocytosis of liposomes by real-time electrical impedance spectroscopy

Evaluation and understanding the effect of drug delivery in in vitro systems is fundamental in drug discovery. We present an assay based on real-time electrical impedance spectroscopy (EIS) measurements that can be used to follow the internalisation and cytotoxic effect of a matrix metalloproteinase (MMP)-sensitive liposome formulation loaded with oxaliplatin (OxPt) on colorectal cancer cells. The EIS response identified two different cellular processes: (i) a negative peak in the cell index (CI) within the first 5 h, due to onset of liposome endocytosis, followed by (ii) a subsequent CI increase, due to the reattachment of cells until the onset of cytotoxicity with a decrease in CI. Free OxPt or OxPt-loaded Stealth liposomes did not show this two-stage EIS response; the latter can be due to the fact that Stealth cannot be cleaved by MMPs and thus is not taken up by the cells. Real-time bright-field imaging supported the EIS data, showing variations in cell adherence and cell morphology after exposure to the different liposome formulations. A drastic decrease in cell coverage as well as rounding up of cells during the first 5 h of exposure to OxPt-loaded (MMP)-sensitive liposome formulation is reflected by the first negative EIS response, which indicates the onset of liposome endocytosis. Graphical abstract.

Supramolecular Polysaccharide Nanotheranostics that Inhibit Cancer Cells Growth and Monitor Targeted Therapy Response

Targeted anticancer therapies directed against specific molecular drivers of tumors are emerging as effective treatment strategies, however, monitoring their response is still challenging. Current clinical imaging techniques that measure either morphological or metabolic changes in the tumor are not always indicative of clinical outcome due to delayed or variable responses. Here, dual-stage polysaccharide-based supramolecular nanotheranostics (SPN) were designed that enable co-delivery of kinase inhibitor and an activatable imaging probe.

Methods: The SPNs were prepared by supramolecular assembly of two components, polysaccharide construct conjugated with kinase inhibitor-function activatable probe and kinase inhibitor- β-cyclodextrin conjugate. Physiochemical characterization of SPNs including size, stability, zeta potential and pH-responsiveness of the assembly was performed. The efficacy of SPNs in inducing cancer cell death by inhibition of kinase signaling and imaging the response was evaluated in murine BRAFV^600E melanoma (D4M) and triple-negative breast cancer (4T1) cell lines. Finally, the in vivo efficacy was investigated in D4M melanoma tumor model.

Results: The polysaccharide-constructs along with kinase inhibitor- β-cyclodextrin conjugates self-assemble to produce SPNs of around 200 nm in diameter and were stable for over a week under physiologically relevant conditions. The SPNs exhibited enhanced cytotoxic effect and significant inhibition of kinase signaling as compared to the free inhibitor. In vitro imaging studies confirmed their enzyme-activatable therapy response tracking abilities both in cancer cells and tumor spheroids. Furthermore, SPN treated mice exhibited better tumor growth inhibition as compared to the control groups and therapy response could be imaged at both early (24-48h) and later time points.

Conclusion: These findings demonstrate that the supramolecular polysaccharide nanotheranostics can not only inhibit kinase signaling pathway in aggressive tumor, but also monitor targeted therapy response early.

Synthesis, Antiproliferative Effect, and Topoisomerase II Inhibitory Activity of 3-Methyl-2-phenyl-1H-indoles

A series of 3-methyl-2-phenyl-1H-indoles was prepared and investigated for antiproliferative activity on three human tumor cell lines, HeLa, A2780, and MSTO-211H, and some structure-activity relationships were drawn up. The GI₅₀ values of the most potent compounds (32 and 33) were lower than 5 μM in all tested cell lines. For the most biologically relevant derivatives, the effect on human DNA topoisomerase II relaxation activity was investigated, which highlighted the good correlation between the antiproliferative effect and topoisomerase II inhibition. The most potent derivative, 32, was shown to induce the apoptosis pathway. The obtained results highlight 3-methyl-2-phenyl-1H-indole as a promising scaffold for further optimization of compounds with potent antiproliferative and antitopoisomerase II activities.

Diversity of small molecule HIV-1 latency reversing agents identified in low- and high-throughput small molecule screens

The latency phenomenon produced by human immunodeficiency virus (HIV-1) prevents viral clearance by current therapies, and consequently development of a cure for HIV-1 disease represents a formidable challenge. Research over the past decade has resulted in identification of small molecules that are capable of exposing HIV-1 latent reservoirs, by reactivation of viral transcription, which is intended to render these infected cells sensitive to elimination by immune defense recognition or apoptosis. Molecules with this capability, known as latency-reversing agents (LRAs) could lead to realization of proposed HIV-1 cure strategies collectively termed "shock and kill," which are intended to eliminate the latently infected population by forced reactivation of virus replication in combination with additional interventions that enhance killing by the immune system or virus-mediated apoptosis. Here, we review efforts to discover novel LRAs via low- and high-throughput small molecule screens, and summarize characteristics and biochemical properties of chemical structures with this activity. We expect this analysis will provide insight toward further research into optimized designs for new classes of more potent LRAs.

Patient-Oncologist Communication Regarding Oral Chemotherapy During Routine Office Visits

PURPOSE

Although studies in other clinical areas have shown that patient-clinician communication can positively influence adherence to medications, little is known about how oncologists address medication counseling during routine office visits. We describe patient-oncologist office-based discussions of oral chemotherapy treatment.

METHODS

Transcripts of 24 patient-oncologist office visits were obtained from a national database. Patients were aged ≥ 19 years and prescribed capecitabine for colorectal cancer. We developed a structured coding worksheet using medication-counseling concepts previously identified as important to medication adherence and a grounded approach. Two coders reviewed transcripts for oncologists' provision of medication information, assessment of patients' adherence to medication, and the provision of self-management support for management of adverse effects. We assessed interrater reliability with Cohen κ statistics. We describe the counseling concepts present within patient-oncologist conversations and present illustrative quotes to describe how they were discussed.

RESULTS

Oncologists generally provided patients who had yet to initiate therapy comprehensive medication information; those in the midst of treatment received less information. Oncologists discussed patients' continued use of the medication (or discontinuation) among all patients who had initiated therapy (N = 18). How the patient was taking the medication (ie, therapy implementation) was less commonly discussed. Medication adverse effects were also discussed in all encounters. Self-management strategies were commonly provided, albeit mostly in response to a presenting symptom and not preemptively. Patients' use of concurrent medications, financial access to therapy, and assessments of logistical arrangements were discussed more sporadically.

CONCLUSION

Using audio recordings from a national sample of patient-oncologist office visits, we identified several potentially important opportunities to enhance medication counseling among patients prescribed capecitabine for the treatment of colorectal cancer.