Conquering chemoresistance in pancreatic cancer: Exploring novel drug therapies and delivery approaches amidst desmoplasia and hypoxia

Pancreatic cancer poses a significant challenge within the field of oncology due to its aggressive behaviour, limited treatment choices, and unfavourable outlook. With a mere 10% survival rate at the 5-year mark, finding effective interventions becomes even more pressing. The intricate relationship between desmoplasia and hypoxia in the tumor microenvironment further complicates matters by promoting resistance to chemotherapy and impeding treatment efficacy. The dense extracellular matrix and cancer-associated fibroblasts characteristic of desmoplasia create a physical and biochemical barrier that impedes drug penetration and fosters an immunosuppressive milieu. Concurrently, hypoxia nurtures aggressive tumor behaviour and resistance to conventional therapies. a comprehensive exploration of emerging medications and innovative drug delivery approaches. Notably, advancements in nanoparticle-based delivery systems, local drug delivery implants, and oxygen-carrying strategies are highlighted for their potential to enhance drug accessibility and therapeutic outcomes. The integration of these strategies with traditional chemotherapies and targeted agents reveals the potential for synergistic effects that amplify treatment responses. These emerging interventions can mitigate desmoplasia and hypoxia-induced barriers, leading to improved drug delivery, treatment efficacy, and patient outcomes in pancreatic cancer. This review article delves into the dynamic landscape of emerging anticancer medications and innovative drug delivery strategies poised to overcome the challenges imposed by desmoplasia and hypoxia in the treatment of pancreatic cancer.

Targeting triple negative breast cancer stem cells using nanocarriers

Breast cancer is a complex and heterogeneous disease, encompassing various subtypes characterized by distinct molecular features, clinical behaviors, and treatment responses. Categorization of subtypes is based on the presence or absence of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), leading to subtypes such as luminal A, luminal B, HER2-positive, and triple-negative breast cancer (TNBC). TNBC, comprising around 20% of all breast cancers, lacks expression of ER, PR, and HER2 receptors, rendering it unresponsive to targeted therapies and presenting significant challenges in treatment. TNBC is associated with aggressive behavior, high rates of recurrence, and resistance to chemotherapy. Tumor initiation, progression, and treatment resistance in TNBC are attributed to breast cancer stem cells (BCSCs), which possess self-renewal, differentiation, and tumorigenic potential. Surface markers, self-renewal pathways (Notch, Wnt, Hedgehog signaling), apoptotic protein (Bcl-2), angiogenesis inhibition (VEGF inhibitors), and immune modulation (cytokines, immune checkpoint inhibitors) are among the key targets discussed in this review. However, targeting the BCSC subpopulation in TNBC presents challenges, including off-target effects, low solubility, and bioavailability of anti-BCSC agents. Nanoparticle-based therapies offer a promising approach to target various molecular pathways and cellular processes implicated in survival of BSCS in TNBC. In this review, we explore various nanocarrier-based approaches for targeting BCSCs in TNBC, aiming to overcome these challenges and improve treatment outcomes for TNBC patients. These nanoparticle-based therapeutic strategies hold promise for addressing the therapeutic gap in TNBC treatment by delivering targeted therapies to BCSCs while minimizing systemic toxicity and enhancing treatment efficacy.

Engineered upconversion nanocarriers for synergistic breast cancer imaging and therapy: Current state of art

Breast cancer is the most common type of cancer in women and is the second leading cause of cancer-related deaths worldwide. Early diagnosis and effective therapeutic interventions are critical determinants that can improve survival and quality of life in breast cancer patients. Nanotheranostics are emerging interventions that offer the dual benefit of in vivo diagnosis and therapeutics through a single nano-sized carrier. Rare earth metal-doped upconversion nanoparticles (UCNPs) with their ability to convert near-infrared light to visible light or UV light in vivo settings have gained special attraction due to their unique luminescence and tumor-targeting properties. In this review, we have discussed applications of UCNPs in drug and gene delivery, photothermal therapy (PTT), photodynamic therapy (PDT) and tumor targeting in breast cancer. Further, present challenges and future opportunities for UCNPs in breast cancer treatment have also been mentioned.

Synthesis and Preclinical Evaluation of Indole Triazole Conjugates as Microtubule Targeting Agents that are Effective against MCF-7 Breast Cancer Cell Lines

CDATA[Background: Microtubules are considered to be an important therapeutic target for most of the anticancer drugs. These are highly dynamic structures comprising of α-tubulin and β-tubulin which are usually heterodimers and found to be involved in cell movement, intracellular trafficking, and mitosis inhibition of which might kill the tumour cells or inhibit the abnormal proliferation of cells. Most of the tubulin polymerization inhibitors, such as Vinca alkaloids, consist of Indole as the main scaffold. The literature also suggests using triazole moiety in the chemical entities, potentiating the inhibitory activity against cell proliferation. So, in our study, we used indole triazole scaffolds to synthesize the derivatives against tubulin polymerization.

OBJECTIVE

The main objective of this study to synthesize indole triazole conjugates by using environmentally friendly solvents (green chemistry) and click chemistry. To carry out the MTT assay and tubulin polymerization assay for the synthesized indole triazole conjugates.

METHODS

All the synthesized molecules were subjected to molecular docking studies using Schrodinger suite and the structural confirmation was performed by Mass, proton-NMR and carbon-NMR, documented in DMSO and CDCL3. Biological studies were performed using DU145 (prostate cancer), A-549 (lung cancer) and, MCF-7 (breast cancer), cell lines obtained from ATCC were maintained as a continuous culture. MTT assay was performed for the analogues using standard protocol. Cell cycle analysis was carried out using flow cytometry.

RESULTS

The Indole triazole scaffolds were synthesized using the principles of Green chemistry. The triazole formation is mainly achieved by using the Click chemistry approach. Structural elucidation of synthesized compounds was performed using Mass spectroscopy (HR-MS), Proton-Nuclear Magnetic Spectroscopy (¹H-NMR) and Carbon-Nuclear Magnetic Spectroscopy (¹³C-NMR). The XP-docked poses and free energy binding calculations revealed that 2c and 2g molecules exhibited the highest docking affinity against the tubulin-colchicine domain (PDB:1SA0). In vitro cytotoxic assessment revealed that 2c and 2g displayed promising cytotoxicity in MTT assay (with CTC50 values 3.52μM and 2.37μM) which are in good agreement with the computational results. 2c and 2g also arrested 63 and 66% of cells in the G₂/M phase, respectively, in comparison to control cells (10%) and tubulin polymerization inhibition assay revealed that 2c and 2g exhibited significant inhibition of tubulin polymerization with IC₅₀ values of 2.31μM, and 2.62μM, respectively in comparison to Nocodazole, a positive control, resulted in an IC₅₀ value of 2.51μM.

CONCLUSION

Indole triazole hybrids were synthesized using click chemistry, and docking studies were carried out using Schrodinger for the designed molecules. Process Optimization has been done for both the schemes. Twelve compounds (2a-2l) have been successfully synthesized and analytical evaluation was performed using NMR and HR-MS. In vitro evaluation was for the synthesized molecules to check tubulin polymerization inhibition for antiproliferative action. Among the synthesized compounds, 2c and 2g have potent anticancer activities by inhibiting tubulin polymerization.

Polysorbate-80 surface modified nano-stearylamine BQCA conjugate for the management of Alzheimer's disease

Acetylcholinesterase (AChE) inhibitors such as donepezil, galantamine and rivastigmine are used for the management of dementia in Alzheimer's Disease (AD). These drugs elevate endogenous acetylcholine (ACh) levels at the M1 muscarinic receptor in the brain to achieve therapeutic benefits. However, their side effects, such as nausea, vomiting, dizziness, insomnia, loss of appetite, altered heart rate, etc., are related to non-specific peripheral activation of M2-M5 muscarinic subtypes. It is logical, therefore, to develop drugs that selectively activate brain M1 receptors. Unfortunately, the orthosteric site homology among the receptor subtypes does not permit this approach. An alternative approach is to use positive allosteric modulator (PAM) of M1 receptors like benzyl quinolone carboxylic acid (BQCA). PAMs although devoid of M1 agonist activity, however, when bound, enhance the binding affinity of orthosteric ligand, Ach. The current challenge with PAMS is their low brain half-life, permeability, and higher elimination rates. This study reports active targeting of brain M1 receptors using surface modified nano lipid-drug conjugates (LDC) of M1 PAM, BQCA, to treat AD. Polysorbate-80 (P-80) surface modified stearylamine (SA)-BQCA conjugated nanoparticles (BQCA-SA-P80-NPs) were prepared by conjugating BQCA to SA, followed by the formation of nanoparticles (NPs) using P-80 by solvent injection method. The BQCA-SA-P80-NPs are near-spherical with a particle size (PS) of 166.62 ± 1.24 nm and zeta potential (ZP) of 23.59 ± 0.37 mV. In the in vitro cytotoxicity (SH-SY5Y cells) and hemolysis assays, BQCA-SA-P80-NPs, show acceptable safety and compatibility. In mice, Alzheimer's model, BQCA-SA-P80-NPs significantly prevent STZ induced changes in memory, neuronal Aβ1-42, p-Tau, APP, NF-κB, and BACE levels and neuronal cell death, when compared to untreated disease control and naïve BQCA treated group. Further, BQCA-SA-P80-NPs significantly improve the therapeutic efficacy of AChE inhibitor, donepezil (DPZ), indicating its potentiating effects. In vivo biodistribution studies in mice show selective accumulation of BQCA-SA-P80-NPs in the brain, suggesting an improved brain bioavailability and reduced peripheral side effects of BQCA. The study results demonstrate that BQCA-SA-P80-NPs can improve brain bioavailability and therapeutic efficacy of BQCA in AD.

Pulmonary delivery of nanostructured lipid carriers for effective repurposing of salinomycin as an antiviral agent

Coronavirus disease outbreak caused a severe public health burden all over the world. Salinomycin (SAL) is a broad-spectrum antibiotic that had drawn attention in selective targeting of cancer and viral infections. Recent drug screen identified SAL as a potent antiviral agent against SARS-CoV-2. In this hypothesis, we discuss the potential of pulmonary delivery of SAL using nanostructured lipid carriers (NLCs) against SARS-CoV-2.

Plausible mechanisms of Niclosamide as an antiviral agent against COVID-19

Corona virus disease 2019 (COVID-19) pandemic caused 18 440 deaths world wide as of 25 March 2020 and posing a serious threat to public health. There is a need, therefore, for effective therapeutic strategies to cure this disease. However, high attrition rates, substantial costs and slow pace are the major limitations of novel drug discovery. Drug repurposing, by employing 'old' drugs to treat 'new' diseases is an attractive approach in drug discovery. Niclosamide (NIC) is an approved anti-helminthic drug with diverse antiviral mechanisms. In this work we hypothesize, the potential antiviral mechanisms of NIC against COVID-19.

HER2 targeted biological macromolecule modified liposomes for improved efficacy of capecitabine in breast cancer

The present research reports the beneficial effects of surface modified chitosan and tumor-homing peptide conjugated liposomes of capecitabine (CAP) for treating breast cancer. Liposomal formulation of CAP was prepared by film hydration method using cholesterol-THP conjugate (CTHP-CAP-LPs) to achieve active targeting through HER2 receptors. CTHP-CAP-LPs significantly improved the specificity and efficacy of CAP by improving cell uptake, cytotoxicity and tumor regression in tumor bearing mice. CTHP-CAP-LPs, therefore, is a promising approach to improve the anticancer effects of CAP.

Tumor homing peptide modified liposomes of capecitabine for improved apoptotic activity and HER2 targeted therapy in breast cancer: in vitro studies

In the present study, we have formulated a liposomal formulation of cytotoxic agent capecitabine (CAP) to overcome its bioavailability issues. Then we have surface modified CAP loaded liposomes (CAP-LPs) with a tumour homing peptide (THP-CAP-LPs) to achieve site specific delivery to breast cancer cells. We found a significant cellular internalization of THP-CAP-LPs when compared to unmodified CAP-LPs. The cytotoxic effect of CAP was also significantly improved with THP-CAP-LPs by downregulating anti-apoptotic proteins and upregulating pro-apoptotic proteins as observed by Western blot analysis. THP-CAP-LPs mediated delivery of CAP can be, therefore, a promising approach for improving antitumor activity and reducing off-target effects.

CD133 receptor mediated delivery of STAT3 inhibitor for simultaneous elimination of cancer cells and cancer stem cells in oral squamous cell carcinoma

Oral Squamous Cell Carcinoma (OSCC) is one of the major causes of cancer related deaths worldwide. Presence of chemoresistant cancer stem cells is the major reason behind metastasis, tumor relapse and treatment resistance in OSCC. STAT 3 signalling plays a key role in survival of cancer stem cells (CSC's), Epithelial Mesenchymal Transition (EMT) mediated metastasis in OSCC. CD 133 is the surface marker for identification of cancer stem cells. In the present study we hypothesise the selective targeting of CSC's using CD 133 mediated delivery of STAT 3 inhibitor, Niclosamide to specifically target CSC's and Non CSC's.

Possible role of Thiazolidinedione in the management of Type-II Endometrial Cancer

Type-II Endometrial Cancer (EMC) is one of the most common types of gynaecological cancer affecting more than 2.7 million people worldwide. Clinical evidence shows that adipokines levels are abnormally altered in Type-II EMC and reported to be one of the major responsible factor for uncontrolled proliferation and metastasis in Type-II EMC. Reversing the altered adipokine levels, therefore, help to control Type-II EMC proliferation and metastasis. In the present hypothesis we focus on the possible role of Thiazolidinediones in favourably altering the adipokine levels to benefit in the management of Type-II EMC.

Possible role of PPAR-γ and COX-2 receptor modulators in the treatment of Non-Small Cell lung carcinoma

Non-Small Cell lung cancer (NSCLC) accounts for 85% of total lung cancers worldwide, affecting more than 1.5 million people every year. Recent studies reported that lung adenocarcinoma express Peroxisome Proliferator Activated Receptor-γ (PPAR-γ) which is believed to be inactivated due to cytoplasmic accumulation or somatic 'loss of function' of the gene. PPAR-γ reported to play an important role in cell proliferation, cell differentiation and apoptosis via inhibition of NF-kβ pathway. Adenocarcinoma also overexpress cyclooxygenase-2 (COX-2), which is reported to promote angiogenesis and metastasis via TX-A2 production. Therefore, we hypothesize that activation of PPAR-γ (through PPAR-γ agonists) and inhibition of COX-2 (through COX-2 inhibitors) will have beneficial effects in the treatment of NSCLC.

Novel dermacozine-1-carboxamides as promising anticancer agents with tubulin polymerization inhibitory activity

In the present study, novel dermacozine-1-carboxamides (8a–8n) were synthesized and screened for their in vitro cytotoxic activity against three different cancer cell lines: MCF-7 (breast cancer), A-549 (lung cancer) and DU145 (prostate cancer). All the compounds showed more efficiency against the DU145 cell line than against the MCF-7 and A-549 cell lines. Furthermore, 8a (CTC₅₀: 7.02 μM) and 8l (CTC₅₀: 6.32 μM) have been found to be more effective against the DU145 cells as they arrest the cell cycle at the G2/M phase by interfering with tubulin polymerization; these results indicate that these compounds act as potential anti-cancer agents by inhibiting tubulin polymerization.

In the present study, novel dermacozine-1-carboxamides (8a–8n) were synthesized and screened for their in vitro cytotoxic activity against three different cancer cell lines: MCF-7 (breast cancer), A-549 (lung cancer) and DU145 (prostate cancer).

Pharmacological targets of breast cancer stem cells: a review

Breast cancers contain small population of tumor-initiating cells called breast cancer stem cells (BCSCs), which are spared even after chemotherapy. Recently, BCSCs are implicated to be a cause of metastasis, tumor relapse, and therapy resistance in breast cancer. BCSCs have unique molecular mechanisms, which can be targeted to eliminate them. These include surface biomarkers, proteins involved in self-renewal pathways, drug efflux transporters, apoptotic/antiapoptotic proteins, autophagy, metabolism, and microenvironment regulation. The complex molecular mechanisms behind the survival of BCSCs and pharmacological targets for elimination of BCSCs are described in this review.

Nanocarrier based approaches for targeting breast cancer stem cells

Breast cancer stem cells (BCSCs) are heterogeneous subpopulation of tumour initiating cells within breast tumours. They are spared even after chemotherapy and responsible for tumour relapse. Targeting BCSCs is, therefore, necessary to achieve radical cure in breast cancer. Despite the availability of agents targeting BCSCs, their clinical application is limited due to their off-target effects and bioavailability issues. Nanotechnology based drug carriers (nanocarriers) offer various advantages to deliver anti-BCSCs agents specifically to their target sites by overcoming their bioavailability issues. In this review, we describe various strategies for targeting BCSCs using nanocarriers.