Role of gemcitabine in cancer therapy

Hyaluronic acid-conjugated lipid nanocarriers in advancing cancer therapy: A review

Lipid nanoparticles are obtaining significant attention in cancer treatment because of their efficacy at delivering drugs and reducing side effects. These things are like a flexible platform for getting anticancer drugs to the tumor site, especially upon HA modification, a polymer that is known to target tumors overexpressing CD44. HA is promising in cancer therapy because it taregtes tumor cells by binding onto CD44 receptors, which are often upregulated in cancer cells. Lipid nanoparticles are not only beneficial in improving solubility and stability of drugs; they also use the EPR effect, meaning they accumulate more in tumor tissue than in healthy tissue. Adding HA to these nanoparticles expands their biocompatibility and makes them more accurate and specific towards tumor cells. Studies show that HA-modified nanoparticles carrying drugs such as paclitaxel or doxorubicin improve how well cells absorb the drugs, reduce drug resistance, and make tumor shrinking. These nanoparticles can respond to tumor microenvironment stimuli in targeted delivery. This targeted delivery diminishes side effects and improves anti-cancer activity of drugs. Thus, lipid-based nanoparticles conjugated with HA are a promising way to treat cancer by delivering drugs effectively, minimizing side effects, and giving us better therapeutic results.

Facile integration of a binary nano-prodrug with αPD-L1 as a translatable technology for potent immunotherapy of TNBC

Immune checkpoint blockers (ICBs)-based immunotherapy is a favorable approach for efficient triple-negative breast cancer (TNBC) treatment. However, the therapeutic efficacy of ICBs is greatly compromised by immunosuppressive tumor microenvironments (TMEs) and low expression levels of programmed cell death ligand-1 (PD-L1). Herein, we constructed an amphiphilic prodrug by linking a hydrophobic STING agonist, MSA-2 and a hydrophilic chemotherapeutic drug, gemcitabine (GEM) via an ester bond, which can self-assemble into GEM-MSA-2 (G-M) nanoparticles (NPs) with a tumor growth inhibition (TGI) value of 87.1 % in a murine 4T1 transplantation tumor model. Notably, the immunogenic cell death (ICD)-triggering effect of GEM together with the cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) pathway activation properties of MSA-2 enables efficient infiltration of non-exhausting T cells and repolarization of macrophages from M2 to M1 types in the tumor microenvironment for transforming a cold tumor to a hot one. Most importantly, G-M NPs treatment increases the PD-L1 expression levels, thus providing a unique opportunity for further integration with anti-PD-L1 monoclonal antibody (αPD-L1) for eliciting stronger immunity that ultimately leads to a TGI value of 98.0 % in the primary tumor and significantly protects against distal and disseminated tumor rechallenge. Overall, this study presents a minimalist nano-prodrug combined with αPD-L1 as a simple yet robust translatable nanotechnology for potent chemo-immunotherapy of TNBC. STATEMENT OF SIGNIFICANCE: Enhancing the therapeutic efficacy of αPD-L1 for tumor immunotherapy via a translatable technology remains a challenge. We report herein facile integration of a binary nano-prodrug with αPD-L1 for potent immunotherapy of TNBC. An amphiphilic prodrug is constructed by linking a hydrophobic STING agonist, MSA-2 and a hydrophilic chemotherapeutic drug, gemcitabine (GEM) via an ester bond. The resulting self-assembled GEM-MSA-2 (G-M) nanoparticles (NPs) show a tumor growth inhibition (TGI) value of 87.1 % in a murine 4T1 transplantation tumor model. Besides the induced immunogenic cell death (ICD) and activated cGAS-STING pathway, G-M NPs increase the PD-L1 expression levels, providing a unique opportunity for further integration with αPD-L1 to elicit stronger immunity that ultimately leads to a TGI value of 98.0 % in the primary tumor and significantly protects against distal and disseminated tumor rechallenge.

Novel Approaches to Monitor Pharmacokinetics and Metabolism of Gemcitabine-Ibandronate Conjugate in Mice and Dogs

BACKGROUND

The use of the bone-seeking properties of bisphosphonates (BPs) to target the delivery of therapeutic drugs is a promising approach for the treatment of bone metastases. Currently, the most advanced example of this approach is a gemcitabine-ibandronate conjugate (GEM-IB), where the bone-targeting BP ibandronate (IB) is covalently linked to the antineoplastic agent gemcitabine (GEM) via a spacer phosphate group. In the present study, we describe the development of a new analytical platform to evaluate the metabolism and pharmacokinetics of GEM-IB in mice and dogs and the results of proof-of-concept studies assessing the pharmacokinetics of GEM-IB in dogs and mice.

METHODS

We validated analytical platforms to analyze GEM-IB and five of its major metabolites IB, gemcitabine-5'-phosphate (GEMMP), gemcitabine (GEM), 2',2'-difluoro-2'-deoxyuridine-5'-phosphate (dFdUMP), and 2',2'-difluoro-2'-deoxyuridine (dFdU) and performed proof-of-concept pharmacokinetic studies in mice (5 mg/kg i.p.) and dogs (5 mg/kg i.v.).

RESULTS

Intra- and inter-run accuracy and imprecision (3 days) of the assays met the (FDA) acceptance criteria. The proof-of-concept plasma pharmacokinetic studies in mice showed AUCs of 1278, 10,652, 405, 38, 1063, 3389, and 38 h·ng/mL for GEM-IB, IB, GEMMP, dFdU-MP, GEM, and dFdU, respectively. In dog plasma, AUCs of 295, 5725, 83, 11, 1625, and 6569 h·ng/mL were observed for GEM-IB, IB, GEMMP, dFdUMP, GEM, and dFdU.

CONCLUSIONS

Pharmacokinetic studies in dogs and mice showed that GEM-IB is rapidly converted to IB and GEM; dFdU is formed (from GEM) with a delay. The rapid disappearance of GEM-IB from circulation could be explained by a combination of metabolism and rapid distribution to tissue/bone.

Exploring the potential of gemcitabine-metal-organic frameworks in combating pancreatic cancer under ketogenic conditions

BACKGROUND

Inadequate treatment responses, chemotherapy resistance, significant heterogeneity, and lengthy treatment durations create an urgent need for new pancreatic cancer therapies. This study aims to investigate the effectiveness of gemcitabine-loaded nanoparticles enclosed in an organo-metallic framework under ketogenic conditions in inhibiting the growth of MIA-PaCa-2 cells.

METHODS

Gemcitabine was encapsulated in Metal-organic frameworks (MOFs) and its morphology and size distribution were examined using transmission electron microscopy (TEM) and Dynamic light scattering (DLS) with further characterization including FTIR analysis. Various drug groups were established to evaluate their influences on cell cytotoxicity, apoptosis rate, cell cycle distribution, levels of superoxide dismutase (SOD), glutathione peroxidase (GPx), malondialdehyde (MDA), and cell migration.

RESULTS

The gemcitabine-MOF was thoroughly analyzed to determine its size, morphology, and chemical composition, confirming its successful preparation. The treatment results showed an increase in the number of apoptotic cells following gemcitabine-MOF treatment, which was found to be associated with cell cycle arrest in the sub-G1 phase. Moreover, these treatments also resulted in reduced cell migration, decreased activity of antioxidant enzymes (SOD, GPx), and increased accumulation of MDA. Additionally, when exposed to ketogenic conditions (where beta-hydroxybutyrate is present in a glucose-limited medium), there was a further increase in cell cycle arrest, accompanied by a more pronounced decrease in SOD and GPx activity, as well as decreased migration.

CONCLUSION

The use of metal-organic framework to encapsulate gemcitabine yielded notable pro-apoptotic effects in MIA-PaCa-2 cells with which ketogenic conditions had a synergistic effect that can hold promise for improving therapeutic options.

Engineered extracellular vesicles for combinatorial TNBC therapy: SR-SIM-guided design achieves substantial drug dosage reduction

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that has no therapeutic targets, relies on chemotherapeutics for treatment, and is in dire need of novel therapeutic approaches for improved patient outcomes. Extracellular vesicles (EVs) serve as intercellular communicators and have been proposed as ideal drug delivery vehicles. Here, EVs were engineered with RNA nanotechnology to develop TNBC tumor inhibitors. Using super resolved-structured illumination microscopy, EVs were optimized for precise Survivin small interfering RNA (siRNA) conjugated to chemotherapeutics loading and CD44 aptamer ligand decoration, thereby enhancing specificity toward TNBC cells. Conventional treatments typically employ chemotherapy drugs gemcitabine (GEM) and paclitaxel (PTX) at dosages on the order of mg/kg respectively, per injection (intravenous) in mice. In contrast, engineered EVs encapsulating these drugs saw functional tumor growth inhibition at significantly reduced concentrations: 2.2 μg/kg for GEM or 5.6 μg/kg for PTX, in combination with 21.5 μg/kg survivin-siRNA in mice. The result is a substantial decrease in the chemotherapeutic dose required, by orders of magnitude, compared with standard regimens. In vivo and in vitro evaluations in a TNBC orthotopic xenograft mouse model demonstrated the efficacy of this decreased dosage strategy, indicating the potential for decreased chemotherapy-associated toxicity.

Trace elements and metal nanoparticles: mechanistic approaches to mitigating chemotherapy-induced toxicity-a review of literature evidence

Anticancer chemotherapy (ACT) remains a cornerstone in cancer treatment, despite significant advances in pharmacology over recent decades. However, its associated side effect toxicity continues to pose a major concern for both oncology clinicians and patients, significantly impacting treatment protocols and patient quality of life. Current clinical strategies to mitigate ACT-induced toxicity have proven largely unsatisfactory, leaving a critical unmet need to block toxicity mechanisms without diminishing ACT's therapeutic efficacy. This review aims to document the molecular mechanisms underlying ACT toxicity and highlight research efforts exploring the protective effects of trace elements (TEs) and their nanoparticles (NPs) against these mechanisms. Our literature review reveals that the primary driver of ACT toxicity is redox imbalance, which triggers oxidative inflammation, apoptosis, endoplasmic reticulum stress, mitochondrial dysfunction, autophagy, and dysregulation of signaling pathways such as PI3K/mTOR/Akt. Studies suggest that TEs, including zinc, selenium, boron, manganese, and molybdenum, and their NPs, can potentially counteract ACT-induced toxicity by inhibiting oxidative stress-mediated pathways, including NF-κB/TLR4/MAPK/NLRP3, STAT-3/NLRP3, Bcl-2/Bid/p53/caspases, and LC3/Beclin-1/CHOP/ATG6, while also upregulating protective signaling pathways like Sirt1/PPAR-γ/PGC-1α/FOXO-3 and Nrf2/HO-1/ARE. However, evidence regarding the roles of lncRNA and the Wnt/β-catenin pathway in ACT toxicity remains inconsistent, and the impact of TEs and NPs on ACT efficacy is not fully understood. Further research is needed to confirm the protective effects of TEs and their NPs against ACT toxicity in cancer patients. In summary, TEs and their NPs present a promising avenue as adjuvant agents for preventing non-target organ toxicity induced by ACT.

Defining the mode of action of cisplatin combined with NUC-1031, a phosphoramidate modification of gemcitabine

The combination of gemcitabine with platinum agents is a widely used chemotherapy regimen for a number of tumour types. Gemcitabine plus cisplatin remains the current therapeutic choice for biliary tract cancer. Gemcitabine is associated with multiple cellular drug resistance mechanisms and other limitations and has thereforelined in use. NUC-1031 (Acelarin) is a phosphorylated form of gemcitabine, protected by the addition of a phosphoramidate moiety, developed to circumvent the key limitations and generate high levels of the cytotoxic metabolite, dFdCTP. The rationale for combination of gemcitabine and cisplatin is determined by in vitro cytotoxicity. This, however, does not offer an explanation of how these drugs lead to cell death. In this study we investigate the mechanism of action for NUC-1031 combined with cisplatin as a rationale for treatment. NUC-1031 is metabolised to dFdCTP, detectable up to 72 h post-treatment and incorporated into DNA, to stall the cell cycle and cause DNA damage in biliary tract and ovarian cancer cell lines. In combination with cisplatin, DNA damage was increased and occurred earlier compared to monotherapy. The damage associated with NUC-1031 may be potentiated by a second mechanism, via binding the RRM1 subunit of ribonucleotide reductase and perturbing the nucleotide pools; however, this may be mitigated by increased RRM1 expression. The implication of this was investigated in case studies from a Phase I clinical trial to observe whether baseline RRM1 expression in tumour tissue at time of diagnosis correlates with patient survival.

Melanoma-on-a-chip model for anticancer drug injecting delivery method

The pharmaceutical and cosmetic industries are encountering a challenge in adopting new study models for product development. there has been a growing interest in organ-on-a-chip systems, and particularly for generating skin models. While numerous alternatives replicating high-fidelity skin models exist, there is a notable absence of melanoma study's methodology specifically on these microfluidic chips. This work introduces a novel skin-on-a-chip device featuring two microfluidic chambers, facilitating a 3D cell co-culture involving fibroblasts, keratinocytes, and melanoma cells. The design of this organ-on-a-chip has enabled the administration of the anticancer treatment Gemcitabine using an injection system within the chip. The results of this work have shown a significant impact on the co-culture distribution of cells, decreasing the population of cancerous cells after the administration of Gemcitabine. The work presented in this article demonstrates the effectiveness of the chip and the administration method for testing anti-melanoma therapies and position this technology as an enhanced fidelity model for studying melanoma while providing an alternative for real-time monitoring of drug testing.

A real-world pharmacovigilance study of FDA Adverse Event Reporting System (FAERS) for gemcitabine

BACKGROUND

Gemcitabine is widely used in the treatment of various cancers. This study aims to evaluate gemcitabine-associated adverse events (AEs) using the Food and Drug Administration Adverse Event Reporting System (FAERS) database.

RESEARCH DESIGN AND METHODS

We analyzed data spanning from January 2004 to June 2023. Employing reporting odds ratio (ROR) and Bayesian confidence propagation neural network (BCPNN) algorithms, we identified AEs with positive signals in patients administered gemcitabine.

RESULTS

Out of 16,623,939 reports, 23,645 involved gemcitabine as the 'primary suspected (PS)' resulting in 74,306 AEs. Consistent with the reports in the specification and clinical trials, thrombocytopenia, pyrexia, neutropenia, and anemia were the most common AEs. Notably, our study identified some unexpected AEs such as abdominal pain, pleural effusion, ascites, and gastrointestinal hemorrhage, among others. The most significant SOC was 'Blood and lymphatic system disorders'. The median onset time for gemcitabine-related AEs was 24 days (interquartile range [IQR] 6-82 days), with most cases occurring within the initial 30 days following gemcitabine administration.

CONCLUSION

Gemcitabine is associated with a broad spectrum of AEs affecting multiple organ systems, with a notable incidence of hospitalization. The study highlights both expected and unexpected AEs, which could enhance future clinical applications and safety of gemcitabine.

Interleukin-1 receptor 1 deficiency worsens hepatocellular carcinoma, while gemcitabine treatment alleviates the hepatocellular carcinoma-induced increase in intra-hepatic immune cells

BACKGROUND AND AIM

Primary liver cancer, particularly hepatocellular carcinoma (HCC), represents a substantial global health challenge. Although immune checkpoint inhibitors are effective in HCC treatment, several patients still experience disease progression. Interleukin-1 (IL-1) regulates immunity and inflammation. We investigate the role of IL-1 in HCC development and progression and determine the potential therapeutic impact of gemcitabine in treating HCC.

METHODS

Hydrodynamics-based transfection, employing the sleeping beauty transposase system, delivered surrogate tumor antigens, NRAS (NRAS proto-oncogene, GTPase), ShP53, and SB100 to C57BL/6 mice. A basic HCC mouse model was established. Pathogen-free animals were tested for serum and hepatotoxicity. The HCC prognosis was monitored using alanine aminotransferase and aspartate aminotransferase levels. Liver histology immunohistochemistry and mouse splenocyte/intra-hepatic immune cell flow cytometry were conducted. IL-1β levels in human and mouse serum were assessed.

RESULTS

Interleukin-1β levels were elevated in patients with HCC compared with those in non-HCC controls. Hepatic IL-1β levels were higher in HCC mouse models than those in non-HCC mice, suggesting localized hepatic inflammation. IL-1 receptor type 1 (IL-1R1) knockout (IL-1R1-/-) mice exhibited less severe HCC progression than that in wild-type mice, despite the high intra-hepatic IL-1β concentration. IL-1R1-/- mice exhibited increased hepatic levels of myeloid-derived suppressor cells and regulatory T cells, which may exacerbate HCC. Gemcitabine significantly reduced the HCC tumor burden, improved liver conditions, and increased survival rates in HCC mouse models. Gemcitabine reduced the hepatic levels of myeloid-derived suppressor cells and regulatory T cells, potentially alleviating immune suppression in the liver.

CONCLUSIONS

Targeting IL-1 or combining gemcitabine with immunotherapy is a promising approach for treating advanced-stage HCC.

Signaling effect, combinations, and clinical applications of triciribine

Triciribine (TCN) is a tricyclic nucleoside. Its synthesis was first described in 1971. Subsequent studies have indicated that TCN plays a role in inhibiting DNA synthesis and was revealed to possess a higher selectivity for Akt. Although a single dose of TCN demonstrated limited activity in solid tumors at the clinical level, combinations of TCN with various agents, such as specific inhibitors, tyrosine kinase inhibitor dasatinib, ErbB inhibitor tipifarnib, IGF1-R inhibitor NVP-AEW541, mTORC1 inhibitor RAD-001, TNF-related apoptosis-inducing ligand, PPARγ agonist, 1,25(OH)2D3, gemcitabine, and paclitaxel, have been reported to be efficient against various malignancies such as pancreatic, breast, prostate cancer, insulinoma, gut neuroendocrine tumor, and hepatocellular carcinoma at the preclinical level. Other than malignancies, through Akt inhibition activity, TCN has also been demonstrated potential for treating lung injuries, including those encountered in COVID-19 infections.

Evo312: An Evodiamine Analog and Novel PKCβI Inhibitor with Potent Antitumor Activity in Gemcitabine-Resistant Pancreatic Cancer

As an obstinate cancer pancreatic cancer (PC) poses a major challenge due to limited treatment options which include resection surgery, radiation therapy, and gemcitabine-based chemotherapy. In cancer cells, protein kinase C βI (PKCβI) participates in diverse cellular processes, including cell proliferation, invasion, and apoptotic pathways. In the present study, we created a scaffold to develop PKCβI inhibitors using evodiamine-based synthetic molecules. Among the candidate inhibitors, Evo312 exhibited the highest antiproliferative efficacy against PC cells, PANC-1, and acquired gemcitabine-resistant PC cells, PANC-GR. Additionally, Evo312 robustly inhibited PKCβI activity. Mechanistically, Evo312 effectively suppressed the upregulation of PKCβI protein expression, leading to the induction of cell cycle arrest and apoptosis in PANC-GR cells. Furthermore, Evo312 exerted an antitumor activity in a PANC-GR cell-implanted xenograft mouse model. These findings position Evo312 as a promising lead compound for overcoming gemcitabine resistance in PC through novel mechanisms.

Biochemical communication between filament-forming enzymes: Potential Regulatory Roles of Metabolites in Enzyme Co-assemblies with CTP Synthase

A host of metabolic enzymes reversibly self-assemble to form membrane-less, intracellular filaments under normal physiological conditions and in response to stress. Often, these enzymes reside at metabolic control points, suggesting that filament formation affords an additional regulatory mechanism. Examples include cytidine-5'-triphosphate (CTP) synthase (CTPS), which catalyzes the rate-limiting step for the de novo biosynthesis of CTP; inosine-5'-monophosphate dehydrogenase (IMPDH), which controls biosynthetic access to guanosine-5'-triphosphate (GTP); and ∆1-pyrroline-5-carboxylate (P5C) synthase (P5CS) that catalyzes the formation of P5C, which links the Krebs cycle, urea cycle, and proline metabolism. Intriguingly, CTPS can exist in co-assemblies with IMPDH or P5CS. Since GTP is an allosteric activator of CTPS, the association of CTPS and IMPDH filaments accords with the need to coordinate pyrimidine and purine biosynthesis. Herein, a hypothesis is presented furnishing a biochemical connection underlying co-assembly of CTPS and P5CS filaments - potent inhibition of CTPS by glutamate γ-semialdehyde, the open-chain form of P5C.

Evaluation of Gemcitabine and Epigallocatechin-3-Gallate Loaded Solid Lipid Nanoparticles on Benzopyrene Induced Lung Cancer Model Via Intranasal Route: Improved Pharmacokinetics and Safety Profile

The objective of this study was to create a new treatment for lung cancer using solid lipid nanoparticles (SLNs) loaded with gemcitabine (GEM) and epigallocatechin-3-gallate (EGCG) that can be administered through the nose. We analyzed the formulation for its effectiveness in terms of micromeritics, drug release, and anti-cancer activity in the benzopyrene-induced Swiss albino mice lung cancer model. We also assessed the pharmacokinetics, biodistribution, biocompatibility, and hemocompatibility of GEM-EGCG SLNs. The GEM-EGCG SLNs had an average particle size of 93.54 ± 11.02 nm, a polydispersity index of 0.146 ± 0.05, and a zeta potential of -34.7 ± 0.4 mV. The entrapment efficiency of GEM and EGCG was 93.39 ± 4.2% and 89.49 ± 5.1%, respectively, with a sustained release profile for both drugs. GEM-EGCG SLNs had better pharmacokinetics than other treatments, and a high drug targeting index value of 17.605 for GEM and 2.118 for EGCG, indicating their effectiveness in targeting the lungs. Blank SLNs showed no pathological lesions in the liver, kidney, and nasal region validating the safety of SLNs. GEM-EGCG SLNs also showed fewer pathological lesions than other treatments and a lower hemolysis rate of 1.62 ± 0.10%. These results suggest that GEM-EGCG SLNs could effectively treat lung cancer.

Divergent functionalization of alkenes enabled by photoredox activation of CDFA and α-halo carboxylic acids

Herein we present our studies on the solvent-controlled difunctionalization of alkenes utilizing chlorodifluoroacetic acid (CDFA) and α-halo carboxylic acids for the synthesis of γ-lactones, γ-lactams and α,α-difluoroesters. Mechanistic insights revealed that photocatalytic reductive mesolytic cleavage of the C-X bond delivers elusive α-carboxyl alkyl radicals. In the presence of an olefin molecule, this species acts as a unique bifunctional intermediate allowing for stipulated formation of C-O, C-N and C-H bonds on Giese-type adducts via single electron transfer (SET) or hydrogen atom transfer (HAT) events. These protocols exhibit great efficiency across a broad spectrum of readily available α-halo carboxylic acids and are amenable to scalability in both batch and flow. To demonstrate the versatility of this concept, the synthesis of (±)-boivinianin A, its fluorinated analog and eupomatilone-6 natural products was successfully accomplished.

Performance evaluation of the HPLC diode array and evaporative light scattering detection for the implementation of dose-banded gemcitabine infusion bags

BACKGROUND

Dose banding (DB) was used to optimise the individualisation of patient treatments with gemcitabine (Gem) in order to improve workload planning at the pharmacy of the University Hospital Centre of Besançon (UHCB). A new simple and fast high-performance liquid chromatographic (HPLC) method was also developed for the quantification of Gem without dilution of the infusion bags.

METHODS

Individual doses of Gem preparations were retrospectively analysed over a 1-year period to determine the frequency of prepared doses. Using a maximum gap of 7.5% around the doses chosen, the selected Gem standard doses were 1400 mg, 1600 mg, 1800 mg and 2000 mg. Following the DB scheme, the frequency of prescription of standard and individualised Gem doses was analysed over a period of 10 months. The four selected Gem standard doses were aseptically prepared in polyolefin infusion bags. Each series of 20 bags was stocked under refrigerated storage conditions (4°C) for up to 84 days. The quantification of Gem without dilution of the infusion bags was obtained by the development of a HPLC method coupled to a diode array detector (DAD) or an evaporative light scattering detector (ELSD).

RESULTS

During the 10-month period following implementation of the DB, 75.6% of the 1266 prescribed doses were covered by the four standardised preparations. The number of different Gem doses was reduced from 183 to 55. Concerning the Gem quantification, both heteroscedasticity and non-linearity were observed with DAD. Using an ELSD, the trueness values were between 98.59% and 101.52% with excellent repeatability values between 0.66% and 1.42%.

CONCLUSION

A new HPLC method has been developed for the quantification of Gem without dilution of the infusion bags prepared in advance as a result of a target DB scheme successfully implemented in our pharmacy department.

Targeting Intracranial Tumours with a Combination of RNA and Chemotherapy

Glioblastoma multiforme (GBM) is a fast-growing and aggressive brain tumour, which remains largely resistant to treatment; the prognosis for patients is poor, with a median survival time of about 12-18 months, post diagnosis. In an effort to bring more efficacious treatments to patients, we targeted the down regulation of ITCH, an E3 ligase that is overexpressed in a variety of cancers, and which inhibits P73, a tumour suppressor gene. 6-O-glycolchitosan (GC) was used to deliver siRNA ITCH (GC60-siRNA-ITCH) and gemcitabine via the nose to brain route in CD-1 nude mice which had previously been implanted intracranially with U87-MG-luc2 cells. Prior to this in vivo study, an in vitro study established the synergistic effect of siRNA-ITCH in combination with a chemotherapy drug-gemcitabine. A downregulation of ITCH, an upregulation of p73 and enhanced apoptosis were observed in vitro in U87-MG cells, using qPCR, Western blot analysis, confocal laser scanning microscopy, flow cytometry and cytotoxicity assays. When GC60-siRNA-ITCH was combined with gemcitabine, there was a resultant decrease in cell proliferation in vitro. In CD1 mice, the administration of siRNA-ITCH (7 doses of 0.081 mg/kg) alone did not significantly affect animal survival (increasing mean survival from 29 to 33 days when compared to untreated animals), whereas intranasal gemcitabine had a significant effect on survival (increasing survival from 29 to 45 days when compared to untreated animals, p < 0.01). The most significant effect was seen with combination therapy (GC60-siRNA-ITCH plus gemcitabine), where survival increased by 89%, increasing from 29 to 54 days (p < 0.01). Our data demonstrate that siRNA chemosensitises brain tumours to gemcitabine and that the nose-to-brain delivery route may be a viable route for the treatment of intracranial tumours.

The double life of a chemotherapy drug: Immunomodulatory functions of gemcitabine in cancer

Although the development of immunotherapies has been revolutionary in the treatment of several cancers, many cancer types remain unresponsive to immune-based treatment and are largely managed by chemotherapy drugs. However, chemotherapeutics are not infallible and are frequently rendered ineffective as resistance develops from prolonged exposure. Recent investigations have indicated that some chemotherapy drugs have additional functions beyond their normative cytotoxic capacity and are in fact immune-modifying agents. Of the pharmaceuticals with identified immune-editing properties, gemcitabine is well-studied and of interest to clinicians and scientists alike. Gemcitabine is a chemotherapy drug approved for the treatment of multiple cancers, including breast, lung, pancreatic, and ovarian. Because of its broad applications, relatively low toxicity profile, and history as a favorable combinatory partner, there is promise in the recharacterization of gemcitabine in the context of the immune system. Such efforts may allow the identification of suitable immunotherapeutic combinations, wherein gemcitabine can be used as a priming agent to improve immunotherapy efficacy in traditionally insensitive cancers. This review looks to highlight documented immunomodulatory abilities of one of the most well-known chemotherapy agents, gemcitabine, relating to its influence on cells and proteins of the immune system.

PRMT1 promotes pancreatic cancer development and resistance to chemotherapy

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal types of cancer, and novel treatment regimens are direly needed. Epigenetic regulation contributes to the development of various cancer types, but its role in the development of and potential as a therapeutic target for PDAC remains underexplored. Here, we show that PRMT1 is highly expressed in murine and human pancreatic cancer and is essential for cancer cell proliferation and tumorigenesis. Deletion of PRMT1 delays pancreatic cancer development in a KRAS-dependent mouse model, and multi-omics analyses reveal that PRMT1 depletion leads to global changes in chromatin accessibility and transcription, resulting in reduced glycolysis and a decrease in tumorigenic capacity. Pharmacological inhibition of PRMT1 in combination with gemcitabine has a synergistic effect on pancreatic tumor growth in vitro and in vivo. Collectively, our findings implicate PRMT1 as a key regulator of pancreatic cancer development and a promising target for combination therapy.

Gemcitabine Modulates HLA-I Regulation to Improve Tumor Antigen Presentation by Pancreatic Cancer Cells

Pancreatic cancer is a lethal disease, harboring a five-year overall survival rate of only 13%. Current treatment approaches thus require modulation, with attention shifting towards liberating the stalled efficacy of immunotherapies. Select chemotherapy drugs which possess inherent immune-modifying behaviors could revitalize immune activity against pancreatic tumors and potentiate immunotherapeutic success. In this study, we characterized the influence of gemcitabine, a chemotherapy drug approved for the treatment of pancreatic cancer, on tumor antigen presentation by human leukocyte antigen class I (HLA-I). Gemcitabine increased pancreatic cancer cells' HLA-I mRNA transcripts, total protein, surface expression, and surface stability. Temperature-dependent assay results indicated that the increased HLA-I stability may be due to reduced binding of low affinity peptides. Mass spectrometry analysis confirmed changes in the HLA-I-presented peptide pool post-treatment, and computational predictions suggested improved affinity and immunogenicity of peptides displayed solely by gemcitabine-treated cells. Most of the gemcitabine-exclusive peptides were derived from unique source proteins, with a notable overrepresentation of translation-related proteins. Gemcitabine also increased expression of select immunoproteasome subunits, providing a plausible mechanism for its modulation of the HLA-I-bound peptidome. Our work supports continued investigation of immunotherapies, including peptide-based vaccines, to be used with gemcitabine as new combination treatment modalities for pancreatic cancer.

Catalysts of Healing: A Symphony of Synthesis and Clinical Artistry in Small-Molecule Agents for Breast Cancer Alleviation

Breast cancer, characterized by its molecular intricacy, has witnessed a surge in targeted therapeutics owing to the rise of small-molecule drugs. These entities, derived from cutting-edge synthetic routes, often encompassing multistage reactions and chiral synthesis, target a spectrum of oncogenic pathways. Their mechanisms of action range from modulating hormone receptor signaling and inhibiting kinase activity, to impeding DNA damage repair mechanisms. Clinical applications of these drugs have resulted in enhanced patient survival rates, reduction in disease recurrence, and improved overall therapeutic indices. Notably, certain molecules have showcased efficacy in drug-resistant breast cancer phenotypes, highlighting their potential in addressing treatment challenges. The evolution and approval of small-molecule drugs have ushered in a new era for breast cancer therapeutics. Their tailored synthetic pathways and defined mechanisms of action have augmented the precision and efficacy of treatment regimens, paving the way for improved patient outcomes in the face of this pervasive malignancy. The present review embarks on a detailed exploration of small-molecule drugs that have secured regulatory approval for breast cancer treatment, emphasizing their clinical applications, synthetic pathways, and distinct mechanisms of action.

Quantitative Analysis of 2D EXSY NMR Spectra of Strongly Coupled Spin Systems in Transmembrane Exchange

Solute translocation by membrane transport proteins is a vital biological process that can be tracked, on the sub-second timescale, using nuclear magnetic resonance (NMR). Fluorinated substrate analogues facilitate such studies because of high sensitivity of 19 F NMR and absence of background signals. Accurate extraction of translocation rate constants requires precise quantification of NMR signal intensities. This becomes complicated in the presence of J-couplings, cross-correlations, and nuclear Overhauser effects (NOE) that alter signal integrals through mechanisms unrelated to translocation. Geminal difluorinated motifs introduce strong and hard-to-quantify contributions from non-exchange effects, the nuanced nature of which makes them hard to integrate into data analysis methodologies. With analytical expressions not being available, numerical least squares fitting of theoretical models to 2D spectra emerges as the preferred quantification approach. For large spin systems with simultaneous coherent evolution, cross-relaxation, cross-correlation, conformational exchange, and membrane translocation between compartments with different viscosities, the only available simulation framework is Spinach. In this study, we demonstrate GLUT-1 dependent membrane transport of two model sugars featuring CF2 and CF2 CF2 fluorination motifs, with precise determination of translocation rate constants enabled by numerical fitting of 2D EXSY spectra. For spin systems and kinetic networks of this complexity, this was not previously tractable.

A Surprising Repurposing of Central Nervous System Drugs against Squamous Cell Carcinoma of the Bladder, UM-UC-5

The potential benefits of drug repurposing have gained attention as an alternative to developing de novo drugs. The potential of using central nervous system (CNS) drugs as anticancer drugs has been explored in several types of human cancers, such as breast and colon cancer, among others. Here, we examine the effect of the CNS drugs sertraline, paroxetine, and chlorpromazine on human squamous carcinoma cells of the bladder (UM-UC-5). After exposing UM-UC-5 cells to increased concentrations of each drug for 48 h, we assessed their metabolic activity using an MTT assay. Based on those results, we calculated cell viability and the half-maximal inhibitory concentration (IC50) values. The results suggest that the CNS drugs were effective against UM-UC-5 in the order of potency of sertraline > chlorpromazine > paroxetine. Interestingly, sertraline was more potent than 5-fluorouracil (5-FU), a widely used anticancer drug. This study demonstrated, for the first time, the promising anticancer activity of CNS drugs on human bladder cancer cells in vitro and supports the repurposing of CNS drugs to improve cancer treatment. Nevertheless, further studies are necessary to understand their mechanism of action and in vivo activity.

Inhibitory effect of liriopesides B in combination with gemcitabine on human pancreatic cancer cells

Gemcitabine (GEM) is a standard chemotherapeutic agent for patients with pancreatic cancer; however, GEM-based chemotherapy has a high rate of toxicity. A combination of GEM and active constituents from natural products may enhance its therapeutic efficacy and reduce its toxicity. This study investigated the synergistic effects of the combination of liriopesides B (LirB) from Liriope spicata var. prolifera and GEM on human pancreatic cancer cells. The results of our study showed that the combination of LirB and GEM synergistically decreased the viability of pancreatic cancer cells. The combination also caused a strong increase in apoptosis and a strong decrease in cell migration and invasion. Furthermore, LirB combined with GEM had potent inhibitory effects on pancreatic cancer stem cells (CSCs). Studies on the mechanisms of action showed that the combination more potently inhibited protein kinase B (Akt) and nuclear factor kappa B (NF-κB), as well as the downstream antiapoptotic molecules B-cell lymphoma 2 (Bcl-2) and survivin than either agent used alone. The results of this study suggest that the combination of LirB with GEM may improve the efficacy of GEM for the treatment of pancreatic cancer.

Electronic spectroscopy of gemcitabine and derivatives for possible dual-action photodynamic therapy applications

In this paper, we explore the molecular basis of combining photodynamic therapy (PDT), a light-triggered targeted anticancer therapy, with the traditional chemotherapeutic properties of the well-known cytotoxic agent gemcitabine. A photosensitizer prerequisite is significant absorption of biocompatible light in the visible/near IR range, ideally between 600 and 1000 nm. We use highly accurate multiconfigurational CASSCF/MS-CASPT2/MM and TD-DFT methodologies to determine the absorption properties of a series of gemcitabine derivatives with the goal of red-shifting the UV absorption band toward the visible region and facilitating triplet state population. The choice of the substitutions and, thus, the rational design is based on important biochemical criteria and on derivatives whose synthesis is reported in the literature. The modifications tackled in this paper consist of: (i) substitution of the oxygen atom at O2 position with heavier atoms (O → S and O → Se) to red shift the absorption band and increase the spin-orbit coupling, (ii) addition of a lipophilic chain at the N7 position to enhance transport into cancer cells and slow down gemcitabine metabolism, and (iii) attachment of aromatic systems at C5 position to enhance red shift further. Results indicate that the combination of these three chemical modifications markedly shifts the absorption spectrum toward the 500 nm region and beyond and drastically increases spin-orbit coupling values, two key PDT requirements. The obtained theoretical predictions encourage biological studies to further develop this anticancer approach.

Cytidine deaminase enzyme activity is a predictive biomarker in gemcitabine-treated cancer patients

BACKGROUND

Gemcitabine is a chemotherapeutic agent, widely used for the treatment of many types of cancer. Cytidine deaminase (CDA) enzyme plays an important role in the metabolism of gemcitabine. This study aimed to assess the power of serum CDA residual activity in predicting drug efficacy and toxicity in gemcitabine-treated cancer patients.

METHODS

This prospective observational study enrolled 63 patients with different types of malignancies who received gemcitabine chemotherapy between May 2019 and January 2022. Blood samples were obtained before the initiation of chemotherapy and serum CDA residual activity was determined using a modification of the Berthelot assay. The patients were followed up for at least 12 months up to 41 months. Overall survival was recorded and treatment-related toxicities were documented according to National Cancer Institute Common Terminology Criteria.

RESULTS

Kaplan-Meier analysis showed that patients with a lower than median CDA value (≤ 8.06 U/mg protein) had a significantly longer survival compared to patients with higher CDA values (> 8.06 U/mg, P ˂ 0.005). Among several potentially involved factors, a significant association between CDA activity and overall survival was observed in univariate analysis (HR = 4.219, 95% CI 1.40-12.74, P = 0.011). On the other hand, the rate of anemia was significantly higher in low-CDA patients compared to high-CDA individuals (P < 0.05).

CONCLUSION

These findings suggest that CDA activity could be a promising biomarker to predict survival and the occurrence of anemia in cancer patients treated with gemcitabine.

The Functional Implications of Broad Spectrum Bioactive Compounds Targeting RNA-Dependent RNA Polymerase (RdRp) in the Context of the COVID-19 Pandemic

BACKGROUND

As long as COVID-19 endures, viral surface proteins will keep changing and new viral strains will emerge, rendering prior vaccines and treatments decreasingly effective. To provide durable targets for preventive and therapeutic agents, there is increasing interest in slowly mutating viral proteins, including non-surface proteins like RdRp.

METHODS

A scoping review of studies was conducted describing RdRp in the context of COVID-19 through MEDLINE/PubMed and EMBASE. An iterative approach was used with input from content experts and three independent reviewers, focused on studies related to either RdRp activity inhibition or RdRp mechanisms against SARS-CoV-2.

RESULTS

Of the 205 records screened, 43 studies were included in the review. Twenty-five evaluated RdRp activity inhibition, and eighteen described RdRp mechanisms of existing drugs or compounds against SARS-CoV-2. In silico experiments suggested that RdRp inhibitors developed for other RNA viruses may be effective in disrupting SARS-CoV-2 replication, indicating a possible reduction of disease progression from current and future variants. In vitro, in vivo, and human clinical trial studies were largely consistent with these findings.

CONCLUSIONS

Future risk mitigation and treatment strategies against forthcoming SARS-CoV-2 variants should consider targeting RdRp proteins instead of surface proteins.

The Evolving Landscape of Antibody-Drug Conjugates: In Depth Analysis of Recent Research Progress

Antibody-drug conjugates (ADCs) are targeted immunoconjugate constructs that integrate the potency of cytotoxic drugs with the selectivity of monoclonal antibodies, minimizing damage to healthy cells and reducing systemic toxicity. Their design allows for higher doses of the cytotoxic drug to be administered, potentially increasing efficacy. They are currently among the most promising drug classes in oncology, with efforts to expand their application for nononcological indications and in combination therapies. Here we provide a detailed overview of the recent advances in ADC research and consider future directions and challenges in promoting this promising platform to widespread therapeutic use. We examine data from the CAS Content Collection, the largest human-curated collection of published scientific information, and analyze the publication landscape of recent research to reveal the exploration trends in published documents and to provide insights into the scientific advances in the area. We also discuss the evolution of the key concepts in the field, the major technologies, and their development pipelines with company research focuses, disease targets, development stages, and publication and investment trends. A comprehensive concept map has been created based on the documents in the CAS Content Collection. We hope that this report can serve as a useful resource for understanding the current state of knowledge in the field of ADCs and the remaining challenges to fulfill their potential.

Biological and clinical significance of the glypican-3 gene in human lung adenocarcinoma: An in silico analysis

Glypican-3 (GPC3), a membrane-bound heparan sulfate proteoglycan, has long been found to be dysregulated in human lung adenocarcinomas (LUADs). Nevertheless, the function, mutational profile, epigenetic regulation, co-expression profile, and clinicopathological significance of the GPC3 gene in LUAD progression are not well understood. In this study, we analyzed cancer microarray datasets from publicly available databases using bioinformatics tools to elucidate the above parameters. We observed significant downregulation of GPC3 in LUAD tissues compared to their normal counterparts, and this downregulation was associated with shorter overall survival (OS) and relapse-free survival (RFS). Nevertheless, no significant differences in the methylation pattern of GPC3 were observed between LUAD and normal tissues, although lower promoter methylation was observed in male patients. GPC3 expression was also found to correlate significantly with infiltration of B cells, CD8+, CD4+, macrophages, neutrophils, and dendritic cells in LUAD. In addition, a total of 11 missense mutations were identified in LUAD patients, and ~1.4% to 2.2% of LUAD patients had copy number amplifications in GPC3. Seventeen genes, mainly involved in dopamine receptor-mediated signaling pathways, were frequently co-expressed with GPC3. We also found 11 TFs and 7 miRNAs interacting with GPC3 and contributing to disease progression. Finally, we identified 3 potential inhibitors of GPC3 in human LUAD, namely heparitin, gemcitabine and arbutin. In conclusion, GPC3 may play an important role in the development of LUAD and could serve as a promising biomarker in LUAD.

Hazard assessment of antineoplastic drugs and metabolites using cytotoxicity and genotoxicity assays

Antineoplastic drugs are among the most toxic pharmaceuticals. Their release into the aquatic ecosystems has been reported, giving rise to concerns about the adverse effects, including cytotoxicity and genotoxicity, that they may have on exposed organisms. In this study, we analyzed the cytotoxicity and genotoxicity of 5-fluorouracil (5-FU) and its metabolite alpha-fluoro-beta-alanine (3-NH2-F); gemcitabine (GEM) and its metabolite 2'-deoxy-2',2'-difluorouridine (2-DOH-DiF); as well as cyclophosphamide (CP) on the HepG2 cell line. Drug concentrations were based on those previously observed in the effluent of a major cancer hospital in Brazil. The study found that GEM, 2-DOH-DiF and 5-FU resulted in reduced cell viability. No reduction in cell viability was observed for CP and 3-NH2-F. Genotoxic assessment revealed damage in the form of nucleoplasmic bridges for CP and 3-NH2-F. The tested concentrations of all compounds resulted in significantly increased MNi and NBUDs. The results showed that these compounds induced cytotoxic and genotoxic effects in HepG2 cells at concentrations found in the environment. To the best of our knowledge, this study is the first to report on the cytogenotoxic impacts of the metabolites 3-NH2-F and 2-DOH-DiF in HepG2 cells. These findings may help in the development of public policies that could minimize potential environmental contamination.

p21 promotes gemcitabine tolerance in A549 cells by inhibiting DNA damage and altering the cell cycle

Gemcitabine is one of the most widely used chemotherapy drugs for advanced malignant tumors, including non-small cell lung cancer. However, the clinical efficacy of gemcitabine is limited due to drug resistance. The aim of the present study was to investigate the role of p21 in gemcitabine-resistant A549 (A549/G+) lung cancer cells. IC50 values were determined using a Cell Counting Kit-8 (CCK-8) assay. mRNA and protein expression levels of genes were measured by reverse transcription-quantitative PCR and western blotting, respectively. The cell cycle distribution and apoptosis rate were analyzed by flow cytometry. DNA damage in cells was evaluated by single-cell gel electrophoresis. The results of western blot analysis and the CCK-8 assay demonstrated that the expression of p21 was higher in A549/G+ cells than in gemcitabine-sensitive cells. Knockdown of p21 expression in gemcitabine-resistant cells sensitized these cells to gemcitabine (with the IC50 decreasing from 84.2 to 26.7 µM). Cell cycle analysis revealed different changes in the cell cycle distribution in A549/G+ cells treated with the same concentration of gemcitabine, and decreased expression of p21 was shown to promote G1 arrest. The apoptosis assay and comet assay results revealed that decreased p21 expression resulted in accumulation of unrepaired DNA double-strand breaks (DSBs) and induction of apoptosis by gemcitabine. The present study demonstrated that knockout of p21 mRNA expression in A549/G+ cells promotes apoptosis and DNA DSB accumulation, accompanied by G1 arrest. These results indicated that p21 is involved in regulating the response of A549 cells to gemcitabine.

JNTX-101, a novel albumin-encapsulated gemcitabine prodrug, is efficacious and operates via caveolin-1-mediated endocytosis

Albumin is an attractive candidate carrier for the development of novel therapeutic drugs. Gemcitabine has been FDA approved for the treatment of solid tumors; however, new drugs that optimize gemcitabine delivery are not available for clinical use. The aim of this study was to test the efficacy of a novel albumin-encapsulated gemcitabine prodrug, JNTX-101, and investigate whether Cav-1 expression predicts the therapeutic efficacy of JNTX-101. We first determined the treatment efficacy of JNTX-101 in a panel of pancreatic/lung cancer cell lines and found that increases in Cav-1 expression resulted in higher uptake of albumin, while Cav-1 depletion attenuated the sensitivity of cells to JNTX-101. In addition, decreased Cav-1 expression markedly reduced JNTX-101-induced apoptotic cell death in a panel of cells, particularly in low-serum conditions. Furthermore, we tested the therapeutic efficacy of JNTX-101 in xenograft models and the role of Cav-1 in JNTX-101 sensitivity using a Tet-on-inducible tumor model in vivo. Our data suggest that JNTX-101 effectively inhibits cell viability and tumor growth, and that Cav-1 expression dictates optimal sensitivity to JNTX-101. These data indicate that Cav-1 correlates with JNTX-101 sensitivity, especially under nutrient-deprived conditions, and supports a role for Cav-1 as a predictive biomarker for albumin-encapsulated therapeutics such as JNTX-101.

Synthesis of Functionalized Five-Membered Heterocycles from Epoxides: A Hydrogen-Bond Donor Catalytic Approach

The synthesis of highly functionalized five-membered oxa- and aza-heterocycles has been reported utilizing hydrogen-bond donor (HBD) catalysis. In this method, an epoxide was taken as a substrate and reacted with functionalized arylidene/alkylidene malononitrile derivatives in the presence of a newly designed HBD catalyst. In all the cases, the products 2,5-disubstituted tetrahydrofurans (2,5-THFs) were obtained in good to excellent yields (up to 86%) with high diastereoselectivity (dr up to 99:1) as a single regioisomer. The stereochemistry at the 2- and 5-positions of the five-membered ring has been confirmed by single-crystal X-ray analysis, and cis is found to be the major product. The same strategy has been further utilized to obtain substituted oxazolidines whenever the epoxide has been reacted with isocyanate as an electrophile. In order to induce enantioselectivity, a chiral epoxide has been reacted with both the electrophiles in the presence of the same catalyst system to afford the single stereoisomer of the final products. This synthetic methodology involves a low catalyst loading and ambient reaction condition and has been generalized with various substituents present in the starting electrophiles to produce the resultant products in acceptable yields and stereoselectivity.

Nucleoside-based anticancer drugs: Mechanism of action and drug resistance

Nucleoside-based drugs, recognized as purine or pyrimidine analogs, have been potent therapeutic agents since their introduction in 1950, deployed widely in the treatment of diverse diseases such as cancers, myelodysplastic syndromes, multiple sclerosis, and viral infections. These antimetabolites establish complex interactions with cellular molecular constituents, primarily via activation of phosphorylation cascades leading to consequential interactions with nucleic acids. However, the therapeutic efficacy of these agents is frequently compromised by the development of drug resistance, a continually emerging challenge in their clinical application. This comprehensive review explores the mechanisms of resistance to nucleoside-based drugs, encompassing a wide spectrum of phenomena from alterations in membrane transporters and activating kinases to changes in drug elimination strategies and DNA damage repair mechanisms. The critical analysis in this review underlines complex interactions of drug and cell and also guides towards novel therapeutic strategies to counteract resistance. The development of targeted therapies, novel nucleoside analogs, and synergistic drug combinations are promising approaches to restore tumor sensitivity and improve patient outcomes.

Real-world efficacy of adjuvant single-agent intravesical gemcitabine for non-muscle invasive bladder cancer

INTRODUCTION

Failure, intolerance, or shortage of bacillus Calmette-Guerin (BCG) treatment for patients with high-risk (HR) non-muscle invasive bladder cancer (NMIBC) leave many facing the prospect of radical cystectomy (RC). However, despite the lack of large-scale randomized controlled studies with single-agent intravesical gemcitabine (Gem), it has emerged as a popular salvage agent after BCG failure or even a treatment alternative to BCG.

AREAS COVERED

1. Characterization of treatment regimen details pertaining to single-agent intravesical adjuvant Gem use among disease states of NMIBC characterized by risk and BCG exposure. 2. Comparison of safety and efficacy of Gem according to risk category, type of tumor (papillary vs. carcinoma in situ (CIS)), and tumor grades.

EXPERT OPINION

Two randomized studies in early BCG failure disease demonstrate that single-agent Gem has superior efficacy versus repeated BCG therapy or mitomycin C. Studies enrolling patients with predominantly papillary disease without CIS, intermediate-risk (IR) disease, and less BCG exposure appear to derive the highest benefits from adjuvant Gem in terms of recurrence and progression. However, studies with cohorts enriched for a predominance of CIS, HR disease and/or more extensive BCG failure have poorer 2-year recurrence free survival and a somewhat higher risk of progression and RC.

Biomedical,clinical and environmental applications of platinum-based nanohybrids: An updated review

Platinum nanoparticles (Pt NPs) have numerous applications in various sectors, including pharmacology, nanomedicine, cancer therapy, radiotherapy, biotechnology and environment mitigation like removal of toxic metals from wastewater, photocatalytic degradation of toxic compounds, adsorption, and water splitting. The multifaceted applications of Pt NPs because of their ultra-fine structures, large surface area, tuned porosity, coordination-binding, and excellent physiochemical properties. The various types of nanohybrids (NHs) of Pt NPs can be fabricated by doping with different metal/metal oxide/polymer-based materials. There are several methods to synthesize platinum-based NHs, but biological processes are admirable because of green, economical, sustainable, and non-toxic. Due to the robust physicochemical and biological characteristics of platinum NPs, they are widely employed as nanocatalyst, antioxidant, antipathogenic, and anticancer agents. Indeed, Pt-based NHs are the subject of keen interest and substantial research area for biomedical and clinical applications. Hence, this review systematically studies antimicrobial, biological, and environmental applications of platinum and platinum-based NHs, predominantly for treating cancer and photo-thermal therapy. Applications of Pt NPs in nanomedicine and nano-diagnosis are also highlighted. Pt NPs-related nanotoxicity and the potential and opportunity for future nano-therapeutics based on Pt NPs are also discussed.

Exploring the Inclusion Complex of an Anticancer Drug with β-Cyclodextrin for Reducing Cytotoxicity Toward the Normal Human Cell Line by an Experimental and Computational Approach

The toxicity of any drug against normal cells is a health hazard for all humans. At present, health and disease researchers from all over the world are trying to synthesize designer drugs with diminished toxicity and side effects. The purpose of the present study is to enhance the bioavailability and biocompatibility of gemcitabine (GEM) by decreasing its toxicity and reducing deamination during drug delivery by incorporating it inside the hydrophobic cavity of β-cyclodextrin (β-CD) without affecting the drug ability of the parent compound (GEM). The newly synthesized inclusion complex (IC) was characterized by different physical and spectroscopic techniques, thereby confirming the successful incorporation of the GEM molecule into the nanocage of β-CD. The molecular docking study revealed the orientation of the GEM molecule into the β-CD cavity (-5.40 kcal/mol) to be stably posed for ligand binding. Photostability studies confirmed that the inclusion of GEM using β-CD could lead to better stabilization of GEM (≥96%) for further optical and clinical applications. IC (GEM-β-CD) and GEM exhibited effective antibacterial and antiproliferative activities without being metabolized in a dose-dependent manner. The CT-DNA analysis showed sufficiently strong IC (GEM-β-CD) binding (Ka = 8.1575 × 1010), and this interaction suggests that IC (GEM-β-CD) may possibly exert its biological effects by targeting nucleic acids in the host cell. The newly synthesized biologically active IC (GEM-β-CD), a derivative of GEM, has pharmaceutical development potentiality.

Shielding and nurturing: Fibronectin as a modulator of cancer drug resistance

Resistance to chemotherapy and targeted therapies constitute a common hallmark of most cancers and represent a dominant factor fostering tumor relapse and metastasis. Fibronectin, an abundant extracellular matrix glycoprotein, has long been proposed to play an important role in the pathobiology of cancer. Recent research has unraveled the role of Fibronectin in the onset of chemoresistance against a variety of antineoplastic drugs including DNA-damaging agents, hormone receptor antagonists, tyrosine kinase inhibitors, microtubule destabilizing agents, etc. The current review summarizes the role played by Fibronectin in mediating drug resistance against diverse anticancer drugs. We have also discussed how the aberrant expression of Fibronectin drives the oncogenic signaling pathways ultimately leading to drug resistance through the inhibition of apoptosis, promotion of cancer cell growth and proliferation.

Mycoplasma infection of cancer cells enhances anti-tumor effect of oxidized methylcytidines

Oxidized methylcytidines 5-hydroxymethyl-2'deoxycytidine (5hmdC) and 5-formy-2'deoxycytidine (5fdC) are deaminated by cytidine deaminase (CDA) into genome-toxic variants of uridine, triggering DNA damage and cell death. These compounds are promising chemotherapeutic agents for cancer cells that are resistant to pyrimidine derivative drugs, such as decitabine and cytarabine, which are inactivated by CDA. In our study, we found that cancer cells infected with mycoplasma exhibited a markedly increased sensitivity to 5hmdC and 5fdC, which was independent of CDA expression of cancer cells. In vitro biochemical assay showed that the homologous CDA protein from mycoplasma was capable of deaminating 5hmdC and 5fdC into their uridine form. Moreover, mycoplasma infection increased the sensitivity of cancer cells to 5hmdC and 5fdC, whereas administration of Tetrahydrouridine (THU) attenuated this effect, suggesting that mycoplasma CDA confers a similar effect as human CDA. As mycoplasma infection occurs in many primary tumors, our findings suggest that intratumoral microbes could enhance the tumor-killing effect and expand the utility of oxidized methylcytidines in cancer treatment.

A metal-dependent conformational change provides a structural basis for the inhibition of CTP synthase by gemcitabine-5'-triphosphate

CTP synthases (CTPS) catalyze the de novo production of CTP using UTP, ATP, and l-glutamine with the anticancer drug metabolite gemcitabine-5'-triphosphate (dF-dCTP) being one of its most potent nucleotide inhibitors. To delineate the structural origins of this inhibition, we solved the structures of Escherichia coli CTPS (ecCTPS) in complex with CTP (2.0 Å), 2'-ribo-F-dCTP (2.0 Å), 2'-arabino-F-CTP (2.4 Å), dF-dCTP (2.3 Å), dF-dCTP and ADP (2.1 Å), and dF-dCTP and ATP (2.1 Å). These structures revealed that the increased binding affinities observed for inhibitors bearing the 2'-F-arabino group (dF-dCTP and F-araCTP), relative to CTP and F-dCTP, arise from interactions between the inhibitor's fluorine atom exploiting a conserved hydrophobic pocket formed by F227 and an interdigitating loop from an adjacent subunit (Q114-V115-I116). Intriguingly, crystal structures of ecCTPS•dF-dCTP complexes in the presence of select monovalent and divalent cations demonstrated that the in crystallo tetrameric assembly of wild-type ecCTPS was induced into a conformation similar to inhibitory ecCTPS filaments solely through the binding of Na+ -, Mg2+ -, or Mn2+ •dF-dCTP. However, in the presence of potassium, the dF-dCTP-bound structure is demetalated and in the low-affinity, non-filamentous conformation, like the conformation seen when bound to CTP and the other nucleotide analogues. Additionally, CTP can also induce the filament-competent conformation linked to high-affinity dF-dCTP binding in the presence of high concentrations of Mg2+ . This metal-dependent, compacted CTP pocket conformation therefore furnishes the binding environment responsible for the tight binding of dF-dCTP and provides insights for further inhibitor design.

Drug Delivery Systems for Localized Cancer Combination Therapy

With over 2 million cancer cases and over 600,000 cancer-associated deaths predicted in the U.S. for 2022, this life-debilitating disease continuously impacts the lives of people across the nation every day. Therapeutic treatment options for cancer have historically involved chemotherapies to eradicate tumors with cytotoxic mechanisms which can negatively affect the efficacy versus toxicity ratio of treatment. With a need for more directed and therapeutically active options, targeted small-molecule inhibitors and immunotherapies have since emerged to mitigate treatment-associated toxicities. However, aggressive tumors can employ a wide range of defense mechanisms to evade monotherapy treatment altogether, resulting in the recurrence of therapeutically resistant tumors. Therefore, many clinical routines have included combination therapy in which anticancer agents are combined to provide a synergistic attack on tumors. Even with this approach, maximizing the efficacy of cancer treatment is contingent upon the dose of drug that reaches the site of the tumor, so often therapy is administered at the site of a tumor via localized delivery platforms. Commonly used platforms for localized drug delivery include polymeric wafers, nanofibrous scaffolds, and hydrogels where drug combinations can be loaded and delivered synchronously. Attaining synergistic activity from these localized systems is dependent on proper material selection and fabrication methods. Herein, we describe these important considerations for enhancing the efficacy of cancer combination therapy through biodegradable, localized delivery systems.

Application of magnetic solid-phase extraction for sensitive determination of anticancer drugs in urine by means of diamino benzidine tetrachlorohydrate modified magnetic nanoparticles

BACKGROUND

The analysis of drug active molecules and residues in the treatment of cancer is important for the sustainability of human life and therapeutic effects. For this purpose, a new magnetic sorbent was developed to use in solid phase extraction prior to conventional high-performance liquid chromatography (HPLC) analysis of Paclitaxel (PAC) and Gemcitabine (GEM) molecules.

METHODS

In this study, a separation and pre-concentration approach based on magnetic solid phase extraction (MSPE) was proposed for PAC and GEM by means of using a newly synthesized magnetic sorbent. After the MSPE procedure, an HPLC system with a diode array detector (DAD) was used to analyze trace amounts of PAC and GEM anticarcinogenic drugs in urine samples. Surface modification of magnetic Fe₃O₄ nanoparticles was carried out by diaminobenzidinetetrachloro hydrate (DABTC) for the first time and a useful sorbent was obtained for MSPE experiments.

RESULTS

In the proposed method, PAC and GEM molecules were retained on the c in the presence of a pH 5.0 medium and desorbed to 300 μL of acetonitrile: methyl alcohol (1:1) eluent phase before HPLC-DAD analysis. Under the optimized conditions, the limit of detection (LOD) values for PAC and GEM were 1.38 and 1.44 ng mL^-1 while the enhancement factor for PAC and GEM were 139.5 and 145.3, respectively. The relative standard deviations (RSD %) for PAC and GEM were below 3.50% in inter-day repeated experiments by means of model solutions containing 100 ng mL^-1 drug active ingredients.

CONCLUSIONS

Synthesis and characterization of DABTC-Fe₃O₄ nanoparticles were performed using suitable methodologies. Optimization of MSPE was done step by step. And finally, the developed method was successfully applied to urine samples with quantitative recoveries in the range of 99.0% and 105.0%.

Gemcitabine-Induced Myositis in a Luminal B Breast Cancer patient: A Case Report

Human epidermal growth factor receptor-positive breast cancer is an aggressive cancer which represents approximately a quarter of all breast cancers worldwide. Recent advances have led to the development of targeted therapies, such as trastuzumab (H), which have significantly improved prognosis. Such therapies are currently used alongside other chemotherapeutic agents, such as paclitaxel (P) and gemcitabine (G). The most common side effects of PGH combination therapy include thrombocytopenia and anemias. However, there have been no previous reports of myositis resulting from this combination. We report the case of a 54-year-old metastatic breast cancer patient on PGH therapy who developed muscle weakness. The patient was initially treated with trastuzumab, pertuzumab, and paclitaxel. However, pertuzumab was changed to gemcitabine due to severe diarrhea. After the fourth cycle of PGH, the patient presented with muscle weakness and creatine kinase levels of up to 6755 U/L. Magnetic resonance imaging of the femur and pelvis revealed diffuse bilateral myositis, suggesting a diagnosis of gemcitabine-induced myositis. The patient was placed on intravenous fluids and corticosteroids, which resolved her condition. To our knowledge, this is the first report of gemcitabine-induced myositis in a breast cancer patient. Further studies are needed to determine the underlying mechanisms of gemcitabine-induced myositis and develop preventative measures.

Drug-Drug Interactions of Cannabidiol with Standard-of-Care Chemotherapeutics

Cannabidiol (CBD) is an easily accessible and affordable Marijuana (Cannabis sativa L.) plant derivative with an extensive history of medical use spanning thousands of years. Interest in the therapeutic potential of CBD has increased in recent years, including its anti-tumour properties in various cancer models. In addition to the direct anticancer effects of CBD, preclinical research on numerous cannabinoids, including CBD, has highlighted their potential use in: (i) attenuating chemotherapy-induced adverse effects and (ii) enhancing the efficacy of some anticancer drugs. Therefore, CBD is gaining popularity as a supportive therapy during cancer treatment, often in combination with standard-of-care cancer chemotherapeutics. However, CBD is a biologically active substance that modulates various cellular targets, thereby possibly resulting in unpredictable outcomes, especially in combinations with other medications and therapeutic modalities. In this review, we summarize the current knowledge of CBD interactions with selected anticancer chemotherapeutics, discuss the emerging mechanistic basis for the observed biological effects, and highlight both the potential benefits and risks of such combined treatments. Apart from the experimental and preclinical results, we also indicate the planned or ongoing clinical trials aiming to evaluate the impact of CBD combinations in oncology. The results of these and future trials are essential to provide better guidance for oncologists to judge the benefit-versus-risk ratio of these exciting treatment strategies. We hope that our present overview of this rapidly advancing field of biomedicine will inspire more preclinical and clinical studies to further our understanding of the underlying biology and optimize the benefits for cancer patients.

Barriers and opportunities for gemcitabine in pancreatic cancer therapy

Pancreatic ductal adenocarcinoma (PDA) has become one of the leading causes of cancer-related deaths across the world. A lack of durable responses to standard-of-care chemotherapies renders its treatment particularly challenging and largely contributes to the devastating outcome. Gemcitabine, a pyrimidine antimetabolite, is a cornerstone in PDA treatment. Given the importance of gemcitabine in PDA therapy, extensive efforts are focusing on exploring mechanisms by which cancer cells evade gemcitabine cytotoxicity, but strategies to overcome them have not been translated into patient care. Here, we will introduce the standard treatment paradigm for patients with PDA, highlight mechanisms of gemcitabine action, elucidate gemcitabine resistance mechanisms, and discuss promising strategies to circumvent them.

Gemcitabine alters sialic acid binding of the glycocalyx and induces inflammatory cytokine production in cultured endothelial cells

Gemcitabine (GEM) is an anticancer drug inhibiting DNA synthesis. Glomerular thrombotic microangiopathy (TMA) has been reported as an adverse effect. However, the precise mechanism of GEM-induced endothelial injury remains unknown. Cultured human umbilical vein endothelial cells (HUVECs) in the confluent phase were exposed to GEM (5-100 μM) for 48 h and evaluated cell viability and morphology, lectin binding concerning sialic acid of endothelial glycocalyx (GCX), and immunofluorescent staining of platelet-endothelial cell adhesion molecule (PECAM) and vascular endothelial growth factor receptor 2 (VEGFR2). The mRNA expression of α2,6-sialyltransferase (ST6Gal1), sialidase (neuraminidase-1: NEU-1), and interleukin (IL)-1β and IL-6 was also evaluated. GEM exposure at 5 μM induced cellular shrinkage and intercellular dissociation, accompanied by slight attenuation of PECAM and VEGFR2 immunostaining, although cell viability was still preserved. At this concentration, lectin binding showed a reduction of terminal sialic acids in endothelial GCX, probably associated with reduced ST6Gal1 mRNA expression. IL-1β and IL-6 mRNA expression was significantly increased after GEM exposure. GEM reduced terminal sialic acids in endothelial GCX through mRNA suppression of ST6Gal1 and induced inflammatory cytokine production in HUVECs. This phenomenon could be associated with the mechanism of GEM-induced TMA.

Gold Nanoparticles Synthesized by an Aqueous Extract of Codium tomentosum as Potential Antitumoral Enhancers of Gemcitabine

Cancer still poses a global threat, since a lot of tumors remain untreatable despite all the available chemotherapeutic drugs, whose side effects, it must also be noted, still raise concerns. The antitumoral properties of marine seaweeds make them a potential source of new, less toxic, and more active antitumoral agents. Furthermore, these natural extracts can be combined with nanotechnology to increase their efficacy and improve targeting. In this work, a Codium tomentosum (CT) aqueous extract was employed for the green synthesis of gold nanoparticles (Au@CT). The complete characterization of Au@CT was performed by UV-Vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Zeta potential, electron microscopy, X-ray powder diffraction (XRD), high-performance steric exclusion chromatography (HPSEC), and by the determination of their antioxidant capacity. The antiproliferative activity of Au@CT was then tested in hepatic (HEPG-2) and pancreatic (BxPC-3) cell lines. Their potential capacity as enhancers of gemcitabine, a drug frequently used to treat both types of tumors, was also tested. The activity of Au@CT was compared to the activity of the CT extract alone. A synergistic effect with gemcitabine was proven for HEPG-2. Our results showed that gold nanoparticles synthesized from seaweed extracts with antitumoral activity could be a good gemcitabine enhancer.

Augmenting chemotherapy with low-dose decitabine through an immune-independent mechanism

The DNA methyltransferase inhibitor decitabine has classically been used to reactivate silenced genes and as a pretreatment for anticancer therapies. In a variation of this idea, this study explores the concept of adding low-dose decitabine (DAC) following administration of chemotherapy to bolster therapeutic efficacy. We find that addition of DAC following treatment with the chemotherapy agent gemcitabine improves survival and slows tumor growth in a mouse model of high-grade sarcoma. Unlike prior studies in epithelial tumor models, DAC did not induce a robust antitumor T cell response in sarcoma. Furthermore, DAC synergizes with gemcitabine independently of the immune system. Mechanistic analyses demonstrate that the combination therapy induces biphasic cell cycle arrest and apoptosis. Therapeutic efficacy was sequence dependent, with gemcitabine priming cells for treatment with DAC through inhibition of ribonucleotide reductase. This study identifies an apparently unique application of DAC to augment the cytotoxic effects of conventional chemotherapy in an immune-independent manner. The concepts explored in this study represent a promising paradigm for cancer treatment by augmenting chemotherapy through addition of DAC to increase tolerability and improve patient response. These findings have widespread implications for the treatment of sarcomas and other aggressive malignancies.

Gemcitabine-induced digital ischaemia in a patient with metastatic breast cancer

A woman in her 50s with HER2 (human epidermal growth factor receptor 2) positive, estrogen/progesterone receptor negative, metastatic invasive ductal carcinoma of the breast, presented with acral cyanosis and severe throbbing pain after recent administration of gemcitabine. She was treated with aspirin, heparin, amlodipine, topical nitroglycerin and analgesics. Gemcitabine was discontinued permanently. She had a gradual recovery except for a small necrotic area over the right 4th digit. However, surgical intervention was avoided.

Peptide-Drug Conjugates: A New Hope for Cancer Management

Cancer remains the leading cause of death worldwide despite advances in treatment options for patients. As such, safe and effective therapeutics are required. Short peptides provide advantages to be used in cancer management due to their unique properties, amazing versatility, and progress in biotechnology to overcome peptide limitations. Several appealing peptide-based therapeutic strategies have been developed. Here, we provide an overview of peptide conjugates, the better equivalents of antibody-drug conjugates, as the next generation of drugs for required precise targeting, enhanced cellular permeability, improved drug selectivity, and reduced toxicity for the efficient treatment of cancers. We discuss the basic components of drug conjugates and their release action, including the release of cytotoxins from the linker. We also present peptide-drug conjugates under different stages of clinical development as well as regulatory and other challenges.