Battling Chemoresistance in Cancer: Root Causes and Strategies to Uproot Them

Deepening Cisplatin sensitivity on Oral Squamous cell Carcinoma cell lines after PON2 knockdown: A FTIRM investigation

Cisplatin is a platinum-based chemotherapy drug with antimicrobial and antitumoral activity, largely used for a long time in the treatment of several cancers, including the Oral Squamous Cell Carcinoma (OSCC), which is one of the most frequent neoplasms of the oral cavity. Due to its aggressiveness and metastatic invasion, OSCC is characterized by poor outcome, often related also to chemoresistance mechanisms. The intracellular enzyme paraoxonase-2 (PON2) normally acts defending cells from the damages induced by Reactive Oxygen Species. Hence, in cancer cells, this enzyme can shield the potential of cisplatin, triggering a resistance mechanism. Based on this evidence, PON2 knockdown seems to be a valuable way to enhance the effects of chemotherapy, escaping this resistance. In this study, HOC621 and HSC-3 OSCC cell lines submitted to PON2 silencing were analyzed by Fourier Transform Infrared Microspectroscopy to evaluate the time-dependent changes occurring in these cells after cisplatin treatment. Spectral data were statistically analyzed by multivariate and univariate analyses and compared with MTT results. Positive feedback on cisplatin efficacy was found in both cell lines submitted to PON2 knockdown, even if with a different response. In particular, a less growth was found in PON2 silenced HOC 621 cells, respect to HSC-3 ones. Moreover, specific spectral markers (A1172/ATOT, A1053/ATOT, A967/A1080, and A992/ATOT band area ratios) were identified and statistically analyzed (p < 0.05): cellular alterations mainly in nucleic acids and carbohydrates were found in both cell lines, although more evident in HOC 621 ones, which therefore appeared to be more affected by chemotherapy treatment.

Peptide-modified nanoparticles for doxorubicin delivery: Strategies to overcome chemoresistance and perspectives on carbohydrate polymers

Chemotherapy serves as the primary treatment for cancers, facing challenges due to the emergence of drug resistance. Combination therapy has been developed to combat cancer drug resistance, yet it still suffers from lack of specific targeting of cancer cells and poor accumulation at the tumor site. Consequently, targeted administration of chemotherapy medications has been employed in cancer treatment. Doxorubicin (DOX) is one of the most frequently used chemotherapeutics, functioning by inhibiting topoisomerase activity. Enhancing the anti-cancer effects of DOX and overcoming drug resistance can be accomplished via delivery by nanoparticles. This review will focus on the development of peptide-DOX conjugates, the functionalization of nanoparticles with peptides, the co-delivery of DOX and peptides, as well as the theranostic use of peptide-modified nanoparticles in cancer treatment. The peptide-DOX conjugates have been designed to enhance the targeted delivery to cancer cells by interacting with receptors that are overexpressed on tumor surfaces. Moreover, nanoparticles can be modified with peptides to improve their uptake in tumor cells via endocytosis. Nanoparticles have the ability to co-deliver DOX along with therapeutic peptides for enhanced cancer treatment. Finally, nanoparticles modified with peptides can offer theranostic capabilities by facilitating both imaging and the delivery of DOX (chemotherapy).

Gene expression profiling to uncover prognostic and therapeutic targets in colon cancer, combined with docking and dynamics studies to discover potent anticancer inhibitor

Drug resistance poses a major obstacle to the efficient treatment of colorectal cancer (CRC), which is one of the cancers that kill people most often in the United States. Advanced colorectal cancer patients frequently pass away from the illness, even with advancements in chemotherapy and targeted therapies. Developing new biomarkers and therapeutic targets is essential to enhancing prognosis and therapy effectiveness. My goal in this study was to use bioinformatics analysis of microarray data to find possible biomarkers and treatment targets for colorectal cancer. Using an ArrayExpress database, I examined a dataset on colon cancer to find genes that were differentially expressed (DEGs) in tumor versus healthy tissues. Integration of advanced bioinformatics tools provided robust insights into the identification and analysis of EGFR as a key player. STRING and Cytoscape enabled the construction and visualization of protein-protein interaction networks, highlighting EGFR as a hub gene due to its centrality and interaction profile. Functional enrichment analysis through DAVID revealed EGFR's involvement in critical biological pathways, as identified in GO and KEGG analyses. This underscores the power of combining computational tools to uncover significant biomarkers like EGFR. Autodock Vina screening of the NCI diversity dataset identified two potential EGFR inhibitors, ZINC13597410 and ZINC04896472. MD simulation data revealed that ZINC04896472 could be potential anticancer inhibitor. These findings serve as a basis for the creation of novel therapeutic approaches that target EGFR and other discovered pathways in CRC. The suggested strategy may improve the efficacy of CRC therapy and advance personalized medicine.

Role of circRNAs in regulating cell death in cancer: a comprehensive review

Despite multiple diagnostic and therapeutic advances, including surgery, radiation therapy, and chemotherapy, cancer preserved its spot as a global health concern. Prompt cancer diagnosis, treatment, and prognosis depend on the discovery of new biomarkers and therapeutic strategies. Circular RNAs (circRNAs) are considered as a stable, conserved, abundant, and varied group of RNA molecules that perform multiple roles such as gene regulation. There is evidence that circRNAs interact with RNA-binding proteins, especially capturing miRNAs. An extensive amount of research has presented the substantial contribution of circRNAs in various types of cancer. To fully understand the linkage between circRNAs and cancer growth as a consequence of various cell death processes, including autophagy, ferroptosis, and apoptosis, more research is necessary. The expression of circRNAs could be controlled to limit the occurrence and growth of cancer, providing a more encouraging method of cancer treatment. Consequently, it is critical to understand how circRNAs affect various forms of cancer cell death and evaluate whether circRNAs could be used as targets to induce tumor death and increase the efficacy of chemotherapy. The current study aims to review and comprehend the effects that circular RNAs exert on cell apoptosis, autophagy, and ferroptosis in cancer to investigate potential cancer treatment targets.

Progress in the discovery and development of anticancer agents from marine cyanobacteria

Covering 2010-April 2024There have been tremendous new discoveries and developments since 2010 in anticancer research based on marine cyanobacteria. Marine cyanobacteria are prolific sources of anticancer natural products, including the tubulin agents dolastatins 10 and 15 which were originally isolated from a mollusk that feeds on cyanobacteria. Decades of research have culminated in the approval of six antibody-drug conjugates (ADCs) and many ongoing clinical trials. Antibody conjugation has been enabling for several natural products, particularly cyanobacterial cytotoxins. Targeting tubulin dynamics has been a major strategy, leading to the discovery of the gatorbulin scaffold, acting on a new pharmacological site. Cyanobacterial compounds with different mechanisms of action (MOA), targeting novel or validated targets in a range of organelles, also show promise as anticancer agents. Important advances include the development of compounds with novel MOA, including apratoxin and coibamide A analogues, modulating cotranslational translocation at the level of Sec61 in the endoplasmic reticulum, largazole and santacruzamate A targeting class I histone deacetylases, and proteasome inhibitors based on carmaphycins, resembling the approved drug carfilzomib. The pipeline extends with SERCA inhibitors, mitochondrial cytotoxins and membrane-targeting agents, which have not yet advanced clinically since the biology is less understood and selectivity concerns remain to be addressed. In addition, efforts have also focused on the identification of chemosensitizing and antimetastatic agents. The review covers the state of current knowledge of marine cyanobacteria as anticancer agents with a focus on the mechanism, target identification and potential for drug development. We highlight the importance of solving the supply problem through chemical synthesis as well as illuminating the biological activity and in-depth mechanistic studies to increase the value of cyanobacterial natural products to catalyze their development.

Nanoscale strategies: doxorubicin resistance challenges and enhancing cancer therapy with advanced nanotechnological approaches

Doxorubicin (DOX), an anthracycline, is widely used in cancer treatment by interfering RNA and DNA synthesis. Its broad antitumour spectrum makes it an effective therapy for a wide array of cancers. However, the prevailing drug-resistant cancer has proven to be a significant drawback to the success of the conventional chemotherapy regime and DOX has been identified as a major hurdle. Furthermore, the clinical application of DOX has been limited by rapid breakdown, increased toxicity, and decreased half-time life, highlighting an urgent need for more innovative delivery methods. Although advancements have been made, achieving a complete cure for cancer remains elusive. The development of nanoparticles offers a promising avenue for the precise delivery of DOX into the tumour microenvironment, aiming to increase the drug concentration at the target site while reducing side effects. Despite the good aspects of this technology, the classical nanoparticles struggle with issues such as premature drug leakage, low bioavailability, and insufficient penetration into tumours due to an inadequate enhanced permeability and retention (EPR) effect. Recent advancements have focused on creating stimuli-responsive nanoparticles and employing various chemosensitisers, including natural compounds and nucleic acids, fortifying the efficacy of DOX against resistant cancers. The efforts to refine nanoparticle targeting precision to improve DOX delivery are reviewed. This includes using receptor-mediated endocytosis systems to maximise the internalisation of drugs. The potential benefits and drawbacks of these novel techniques constitute significant areas of ongoing study, pointing to a promising path forward in addressing the challenges posed by drug-resistant cancers.

An update understanding of stemness and chemoresistance of prostate cancer

INTRODUCTION

Globally, prostate cancer (CaP) is a leading cause of death and disability among men and a substantial public health burden. Despite advancements in cancer treatment, chemoresistance remains a significant issue in cancer therapy, accounting for the majority of patient relapses and poor survival. Cancer stem cells (CSCs) are considered the main cause of cancer recurrence, chemoresistance, and poor survival of patients. These CSCs acquire stemness and chemoresistance by certain mechanisms such as enhanced DNA repair processes, increased expression of drug efflux pumps, resistance to apoptosis, and altered cell cycle and tumor microenvironment (TME).

AREA COVERED

We cover the latest developments in this field and give an overview of future research directions.

EXPERT OPINION

CSCs show dysregulation of several signaling pathways, mostly related to conferring chemoresistance phenotype, such as high drug efflux, apoptotic resistance, quiescent cell cycle, tumor microenvironment, and DNA repair. There are several research articles published on this topic. However, still, this field warrants further investigations to identify the therapeutic molecule that can either chemosensitize CSCs or kill them effectively. This can only be possible when we know the complete mechanisms to comprehend the fundamental causes of cancer stemness and therapy resistance.

Metformin and the PI3K/AKT signaling pathway: implications for cancer, cardiovascular, and central nervous system diseases

Recent findings have brought our understanding of diseases at the molecular level, highlighting upstream intracellular pathways as potential therapeutic targets. The PI3K/AKT pathway, a key regulator of cellular responses to environmental changes, is frequently altered in various diseases, making it a promising target for intervention. Metformin is the most known anti-diabetic agent that is known due to its effects on cancer, inflammatory-related diseases, oxidative stress, and other human diseases. It is clearly understood that metformin modulates the activity of the PI3K/AKT pathway leading to a wide variety of outcomes. This interaction has been well-studied in various diseases. Therefore, this review aims to examine PI3K/AKT-modulating properties of metformin in cancer, cardiovascular, and central nervous system diseases. Our findings indicate that metformin is effective in treating cancer and CNS diseases, and plays a role in both the prevention and treatment of cardiovascular diseases. These insights support the potential of metformin in comprehensive strategies for disease management.

κ-carrageenan - Gelatin hydrogel embedding carvacrol loaded gold nanobipyramids for treating prostate cancer via fractionated photothermal-chemotherapy

Conventional treatment of prostate cancer need more specificity, and higher efficiency. The present work is the first attempt to utilize hydrogel-loaded carvacrol-based chemotherapy with fractionated photothermal therapy (F-PTT) using a 635 nm laser for its treatment. Gold nanobipyramids (AuNBPs) were used as drug carrier and photosensitizer. A marine-derived hydrogel (AuNBP-HG) was fabricated and physicochemically characterized. A 635 nm NIR light was used for the fractionated PTT in three cycles of treatment on different days at varying power densities for 5 min. The efficiency of single and dual treatments was experimented in vitro and in vivo. The results showed that the dual therapy imparted a better effect than monotherapy. The AuNBP-CVL synthesized was nearly 50 nm and efficiently loaded within AuNBP-HG, displaying thermal responsiveness, a good sol-gel transition, a controlled drug release rate, and high stability. In vitro evaluation demonstrated that the F-PTT evinced stability during temperature rise without damaging healthy surrounding tissue. In vivo study revealed that a stable temperature rise up to 60 °C by the 635 nm NIR light due to photosensitization of AuNBP and sustained CVL release from AuNBP-HG into the tumor microenvironment exhibited successful thermal ablation of the cancer cells. Histological analysis confirmed that the uniform suspension of AuNBP within cancer tissues might have enhanced tumor cell lysis during the dual therapy. Western blot analysis exhibited that the cellular death could result from the upregulation of pJNK and p53 protein. In conclusion, the current study illustrated that dual therapy could be a feasible alternative to non-target specific and invasive traditional therapies against prostate cancer.

Computational Elucidation of Hub Genes and Pathways Correlated with the Development of 5-Fluorouracil Resistance in HCT 116 Colorectal Carcinoma Cell Line

Colorectal cancer (CRC) is the third most deadly cancer diagnosed in both men and women. 5-Fluorouracil (5-FU) treatment frequently causes the CRC cells to become chemoresistance, which has a negative impact on prognosis. Using bioinformatic techniques, this work describes important genes and biological pathways linked to 5-FU resistance in CRC cells. In our studies, a 5-FU-resistant HCT 116 cell line exhibiting elevated TYMS was created and validated using various tests. Bioinformatic studies were conducted to determine which differentially expressed genes (DEGs) were responsible for the establishment of 5-FU resistance in the same cell line. After screening 3949 DEGs from the two public datasets (GSE196900 and GSE153412), 471 overlapping DEGs in 5-FU-resistant HCT 116 cells were chosen. These overlapping DEGs were used to build the PPI network, and a major cluster module containing 21 genes was found. Subsequently, using three topological analysis algorithms, 10 hub genes were identified, which included HLA-DRA, HLA-DRB1, CXCR4, MMP9, CDH1, SMAD3, VIM, SYK, ZEB1, and SELL. Their roles were ascertained by utilizing Gene Ontology keywords and pathway enrichment studies. Our results also demonstrated that the miRNA and transcription factors (TFs) that had the strongest connection with the hub genes were hsa-mir-26a-5p, hsa-mir-30a-5p, RELA, and NFKB1. Ultimately, 84 FDA-approved drugs that target those hub genes were found to potentially treat 5-FU resistance CRC. Our research's findings increase our understanding of the fundamental factors that contribute to the prevalence of 5-FU resistance CRC, which could ultimately assist in the identification of valuable malignancy biomarkers and targeted treatment approaches based on key regulatory pathways.

The crosstalk between SND1 and PDCD4 is associated with chemoresistance of non-small cell lung carcinoma cells

Lung cancer is the leading cause of cancer-related deaths worldwide. Non-small cell lung cancer (NSCLC) is highly resistant to chemo- or radiation therapy, which poses a huge challenge for treatment of advanced NSCLC. Previously, we demonstrated the oncogenic role of Tudor Staphylococcal nuclease (TSN, also known as Staphylococcal nuclease domain-containing protein 1, SND1), in regulating chemoresistance in NSCLC cells. Here, we showed that silencing of SND1 augmented the sensitivity of NSCLC cells to different chemotherapeutic drugs. Additionally, the expression of PDCD4 (a tumor suppressor highly associated with lung cancer) in NSCLC cells with low endogenous levels was attenuated by SND1 silencing, implying that SND1 might function as a molecular regulator upstream of PDCD4. PDCD4 is differentially expressed in various NSCLC cells. In the NSCLC cells (A549 and H23 cells) with low expression of PDCD4, despite the downregulation of PDCD4, silencing of SND1 still led to sensitization of NSCLC cells to treatment with different chemotherapeutic agents by the inhibition of autophagic activity. Thus, a novel correlation interlinking SND1 and PDCD4 in the regulation of NSCLC cells concerning chemotherapy was revealed, which contributes to understanding the mechanisms of chemoresistance in NSCLC.

Omega-3 fatty acids: molecular weapons against chemoresistance in breast cancer

Breast cancer is the most commonly diagnosed type of cancer and the leading cause of cancer-related death in women worldwide. Highly targeted therapies have been developed for different subtypes of breast cancer, including hormone receptor (HR)-positive and human epidermal growth factor receptor 2 (HER2)-positive breast cancer. However, triple-negative breast cancer (TNBC) and metastatic breast cancer disease are primarily treated with chemotherapy, which improves disease-free and overall survival, but does not offer a curative solution for these aggressive forms of breast cancer. Moreover, the development of chemoresistance is a major cause of therapeutic failure in this neoplasia, leading to disease relapse and patient death. In addition, chemotherapy's adverse side effects may substantially worsen health-related quality of life. Therefore, to improve the outcome of patients with breast cancer who are undergoing chemotherapy, several therapeutic options are under investigation, including the combination of chemotherapeutic drugs with natural compounds. Omega-3 (ω-3) polyunsaturated fatty acids (PUFAs), including docosahexaenoic and eicosapentaenoic acids, have drawn attention for their antitumoral properties and their preventive activities against chemotherapy-induced toxicities in breast cancer. A literature review was conducted on PubMed using keywords related to breast cancer, omega-3, chemoresistance, and chemotherapy. This review aims to provide an overview of the molecular mechanisms driving breast cancer chemoresistance, focusing on the role of ω-3 PUFAs in these recognized cellular paths and presenting current findings on the effects of ω-3 PUFAs combined with chemotherapeutic drugs in breast cancer management.

Role of Hypoxia-Associated Long Noncoding RNAs in Cancer Chemo-Therapy Resistance

Hypoxia is a well-known characteristic of the tumor microenvironment which significantly influences cancer development and is closely linked to unfavorable outcomes. Long noncoding RNAs (lncRNAs), which are part of the noncoding genome, have garnered increasing attention because of their varied functions in tumor metastasis. Long noncoding RNAs (lncRNAs) are defined as noncoding RNAs which are longer than 200 nucleotides, and they regulate diverse cellular processes by modulating gene expression at the transcriptional, post-transcriptional and epigenetic levels. Hypoxia is a well-established environmental factor which enhances the metastasis of solid tumors. Epithelial-mesenchymal transition (EMT) represents one of the key mechanisms triggered by hypoxia which contributes to metastasis. Numerous lncRNAs have been identified as being upregulated by hypoxia. These lncRNAs significantly contribute toward cancer cell migration, invasion and metastasis. Recent studies have identified a crucial role for these hypoxia-induced lncRNAs in chemotherapy resistance. These hypoxia-related lncRNAs can be plausible therapeutic targets for devising effective cancer therapies.

HSF1 at the crossroads of chemoresistance: from current insights to future horizons in cell death mechanisms

Heat Shock Factor 1 (HSF1) is a major transcriptional factor regulating the heat shock response and has become a potential target for overcoming cancer chemoresistance. This review comprehensively examines HSF1's role in chemoresistance and its potential as a therapeutic target in cancer. We explore the complex, intricate mechanism that regulates the activation of HSF1, HSF1's function in promoting resistance to chemotherapy, and the strategies used to manipulate HSF1 for therapeutic benefit. In addition, we discuss emerging research implicating HSF1's roles in autophagy, apoptosis, DNA damage repair, drug efflux, and thus chemoresistance. This article highlights the significance of HSF1 in cancer chemoresistance and its potential as a target for enhancing cancer treatment efficacy.

Molecular mechanisms and therapeutic strategies in overcoming chemotherapy resistance in cancer

Cancer remains a leading cause of mortality globally and a major health burden, with chemotherapy often serving as the primary therapeutic option for patients with advanced-stage disease, partially compensating for the limitations of non-curative treatments. However, the emergence of chemotherapy resistance significantly limits its efficacy, posing a major clinical challenge. Moreover, heterogeneity of resistance mechanisms across cancer types complicates the development of universally effective diagnostic and therapeutic approaches. Understanding the molecular mechanisms of chemoresistance and identifying strategies to overcome it are current research focal points. This review provides a comprehensive analysis of the key molecular mechanisms underlying chemotherapy resistance, including drug efflux, enhanced DNA damage repair (DDR), apoptosis evasion, epigenetic modifications, altered intracellular drug metabolism, and the role of cancer stem cells (CSCs). We also examine specific causes of resistance in major cancer types and highlight various molecular targets involved in resistance. Finally, we discuss current strategies aiming at overcoming chemotherapy resistance, such as combination therapies, targeted treatments, and novel drug delivery systems, while proposing future directions for research in this evolving field. By addressing these molecular barriers, this review lays a foundation for the development of more effective cancer therapies aimed at mitigating chemotherapy resistance.

Dynamic P-glycoprotein expression in early and late memory states of human CD8 + T cells and the protective role of ruxolitinib

ABCB1/MDR-1/P-glycoprotein (Pgp) is an ABC transporter responsible for cancer cell multi-drug resistance. It is expressed in cytotoxic T lymphocytes (CTL). Eliminating sensitive cancer cells during high-dose chemotherapy can also damage immune cells. Our study aimed to assess which maturing human CD8 + CTL memory subsets may be affected based on their Pgp protein expression. In an in vitro CTL differentiation model system, we tracked the maturation of naive, effector, and memory cells and the expression of Pgp. This system involves co-culturing blood lymphocytes with proliferation-inhibited JY antigen-presenting B-lymphoblastoid cells expressing HLA-I A2. These JY-primed maturing CTLs were TCR-activated using beads, and the effect of the maturation-modifying JAK1/2 inhibitor ruxolitinib was examined. Multidimensional analysis identified six major CTL subsets: naive, young memory (Tym), stem cell memory (Tscm), central memory (Tcm), effector memory (Tem), and effectors (Te). These subsets were further divided into thirteen specific subsets: TymCD127 + , TymCD127-, Tscm, TcmCD95 + , TcmCD73 +CD95 + , TcmCD95+CD127 + , TcmPD1 + , TemCD95 + , TemraCD127 + , TemraCD127-, TeCD95 + , and TeCD73 +CD95 + . Pgp expression was detectable in naïve cells and dynamically changed across the thirteen identified subsets. Increased Pgp was detected in young memory T cells and in Tscm, TcmCD95 + , and TcmPD1 + human CTL subsets. Unlike other transiently appearing memory cells, the number of cells in these core Pgp-expressing memory subsets stabilized by the end of the contraction phase. Ruxolitinib treatment downregulated effector T-cell polarization while upregulating small memory subsets expressing Pgp. In conclusion, activation increased Pgp expression, whereas ruxolitinib treatment preserved small early and late memory subset core that primarily expressed Pgp.

CMINNs: Compartment model informed neural networks - Unlocking drug dynamics

In the field of pharmacokinetics and pharmacodynamics (PKPD) modeling, which plays a pivotal role in the drug development process, traditional models frequently encounter difficulties in fully encapsulating the complexities of drug absorption, distribution, and their impact on targets. Although multi-compartment models are frequently utilized to elucidate intricate drug dynamics, they can also be overly complex. To generalize modeling while maintaining simplicity, we propose an innovative approach that enhances PK and integrated PK-PD modeling by incorporating fractional calculus or time-varying parameter(s), combined with constant or piecewise constant parameters. These approaches effectively model anomalous diffusion, thereby capturing drug trapping and escape rates in heterogeneous tissues, which is a prevalent phenomenon in drug dynamics. Furthermore, this method provides insight into the dynamics of drug in cancer in multi-dose administrations. Our methodology employs a Physics-Informed Neural Network (PINN) and fractional Physics-Informed Neural Networks (fPINNs), integrating ordinary differential equations (ODEs) with integer/fractional derivative order from compartmental modeling with neural networks. This integration optimizes parameter estimation for variables that are time-variant, constant, piecewise constant, or related to the fractional derivative order. The results demonstrate that this methodology offers a robust framework that not only markedly enhances the model's depiction of drug absorption rates and distributed delayed responses but also unlocks different drug-effect dynamics, providing new insights into absorption rates, anomalous diffusion, drug resistance, persistence, and pharmacokinetic tolerance, all within a system of just two (fractional) ODEs with explainable results. These findings have the potential to streamline drug development by improving the prediction of drug behavior in complex biological systems and shedding light on cancer cell death mechanisms, ultimately aiding in the design of more effective therapeutic strategies.

Quinoline- and coumarin-based ligands and their rhenium(I) tricarbonyl complexes: synthesis, spectral characterization and antiproliferative activity on T-cell lymphoma

Novel 6-substituted 2-(trifluoromethyl)quinoline 5a-5e and coumarin 6a-6d ligands with aldoxime ether linked pyridine moiety were synthesized by O-alkylation of quinoline and coumarin with (E)-picolinaldehyde oxime and subsequently with [Re(CO)5Cl] gave rhenium(I) tricarbonyl complexes 5aRe-5eRe and 6aRe-6dRe that were fully characterized by NMR, single-crystal X-ray diffraction, IR and UV-Vis spectroscopy. The results of antiproliferative evaluation of quinoline and coumarin ligands and their rhenium(I) tricarbonyl complexes on various human tumor cell lines, including acute lymphoblastic leukemia (CCRF-CEM), acute monocytic leukemia (THP1), cervical adenocarcinoma (HeLa), colon adenocarcinoma (CaCo-2), T-cell lymphoma (HuT78), and non-tumor human fibroblasts (BJ) showed that the quinoline complexes 5aRe-5eRe had higher inhibitory activity than coumarin complexes 6aRe-6dRe, particularly against T-cell lymphoma (HuT78) cells. 6-Methoxy-2-(trifluoromethyl)quinoline 5e and 6-methylcoumarin 6d, and their rhenium(I) tricarbonyl complexes 5eRe and 6dRe were found to arrest the cell cycle of HuT78 cells by causing a significant accumulation of cells in the G0/G1 phase and a marked decrease in the number of cells in the G2/M phase. These rhenium(I) tricarbonyl complexes also slightly increased ROS production and significantly decreased the mitochondrial membrane potential by 50 % (5eRe) and 45 % (6dRe) compared to untreated cells and cells treated with 5e and 6d. These results suggest that the cytotoxic effects of these compounds are mediated by their effects on mitochondrial membrane potential and the subsequent increase in ROS production.

Ivermectin Strengthens Paclitaxel Effectiveness in High-Grade Serous Carcinoma in 3D Cell Cultures

BACKGROUND

Chemoresistance is a major obstacle in high-grade serous carcinoma (HGSC) treatment. Although many patients initially respond to chemotherapy, the majority of them relapse due to Carboplatin and Paclitaxel resistance. Drug repurposing has surfaced as a potentially effective strategy that works synergically with standard chemotherapy to bypass chemoresistance. In a prior study, using 2D cultures and two HGSC chemoresistant cell lines, it was demonstrated that combining Carboplatin or Paclitaxel with Pitavastatin or Ivermectin resulted in the most notable synergy. Acknowledging that 2D culture systems are limited in reflecting the tumor architecture, 3D cultures were generated to provide insights on treatment efficacy tests in more complex models.

OBJECTIVES

We aimed to investigate whether combining Carboplatin or Paclitaxel with Pitavastatin or Ivermectin offers therapeutic benefits in a Cultrex-based 3D model.

METHODS

Here, the cytotoxicity of Carboplatin and Paclitaxel, both alone and in combination with Pitavastatin or Ivermectin, were analyzed on two chemoresistant tumor cell lines, OVCAR8 and OVCAR8 PTX R C, in 3D cultures. Cellular viability was assessed using CellTiter-Glo® Luminescent assays. Also, it explored synergistic interactions using zero interaction potency, Loewe, Bliss independence, and High-single agent reference models.

RESULTS

Our research indicates combining chemotherapeutic drugs with Pitavastatin or Ivermectin yields significantly more cytotoxic effects than chemotherapy alone. For all the combinations tested, at least one model indicated an additive effect; however, only the combination of Paclitaxel and Ivermectin consistently demonstrated an additive effect across all chemoresistant cell lines cultured in 3D models, as well as in all four synergy reference models used to assess drug interactions.

CONCLUSIONS

Combining Paclitaxel with Ivermectin has the highest cytotoxic and the strongest additive effect for both chemoresistant cell lines compared to Paclitaxel alone.

Ellagic Acid Induces DNA Damage and Apoptosis in Cancer Stem-like Cells and Overcomes Cisplatin Resistance

Cancer stem cells (CSCs) are responsible for chemoresistance and tumor relapse in many solid malignancies, including lung and ovarian cancer. Ellagic acid (EA), a natural polyphenol, exhibits anticancer effects on various human malignancies. However, its impact and mechanism of action on cancer stem-like cells (CSLCs) are only partially understood. In this study, we evaluated the therapeutic potential and underlying molecular mechanism of EA isolated from tropical mango against CSLCs. Herein, we observed that EA treatment reduces the stem-like phenotypes in cancer cells, thereby lowering the cell survival and self-renewal potential of ovarian and lung CSLCs. Additionally, EA treatment limits the populations of lung and ovarian CSLCs characterized by CD133+ and CD44+CD117+, respectively. A mechanistic investigation showed that EA treatment induces ROS generation by altering mitochondrial dynamics, causing changes in the levels of Drp1 and Mfn2, which lead to an increased level of accumulation of DNA damage and eventually trigger apoptosis in CSLCs. Moreover, pretreatment with EA sensitizes CSLCs to cisplatin treatment by enhancing DNA damage accumulation and impairing the DNA repair ability of the CSLCs. Furthermore, EA pretreatment significantly reduces cisplatin-induced mutation frequency and improves drug retention in CSLCs, potentially suppressing the development of acquired drug resistance. Taken together, our results demonstrate an unreported finding that EA inhibits CSLCs by targeting mitochondrial function and triggering apoptosis. Thus, EA can be used either alone or in combination with other chemotherepeutic drugs for the management of cancer.

The Multifaced Role of Collagen in Cancer Development and Progression

Collagen is a crucial protein in the extracellular matrix (ECM) essential for preserving tissue architecture and supporting crucial cellular functions like proliferation and differentiation. There are twenty-eight identified types of collagen, which are further divided into different subgroups. This protein plays a critical role in regulating tissue homeostasis. However, in solid tumors, the balance can be disrupted, due to an abundance of collagen in the tumor microenvironment, which significantly affects tumor growth, cell invasion, and metastasis. It is important to investigate the specific types of collagens in cancer ECM and their distinct roles in tumor progression to comprehend their unique contribution to tumor behavior. The diverse pathophysiological functions of different collagen types in cancers illustrate collagen's dual roles, offering potential therapeutic options and serving as prognostic markers.

Mechano-assisted strategies to improve cancer chemotherapy

Chemotherapy remains a cornerstone in cancer treatment; however, its effectiveness is frequently undermined by the development of drug resistance. Recent studies underscores the pivotal role of the tumor mechanical microenvironment (TMME) and the emerging field of mechanical nanomedicine in tackling chemo-resistance. This review offers an in-depth analysis of mechano-assisted strategies aimed at mitigating chemo-resistance through the modification of the TMME and the refinement of mechanical nanomedicine delivery systems. We explore the potential of targeting abnormal tumor mechanical properties as a promising avenue for enhancing the efficacy of cancer chemotherapy, which offers novel directions for advancing future cancer therapies, especially from the mechanomedicine perspective.

Efficacy and Safety of Pazopanib in the Treatment of Thyroid Cancer: A Systematic Review

Pazopanib, a multi-targeted tyrosine kinase inhibitor, has been explored for its efficacy in treating various subtypes of thyroid cancer, including differentiated thyroid carcinoma (DTC), medullary thyroid carcinoma (MTC), and anaplastic thyroid carcinoma (ATC). This systematic review assesses the efficacy and safety of pazopanib, focusing on the progression-free survival (PFS), overall survival (OS), and response rates and adverse events. A comprehensive search was conducted in databases including PubMed, Scopus, and Web of Science up to October 2024 to identify randomized controlled trials and phase II clinical trials that investigated the use of pazopanib in thyroid cancer. The PRISMA guidelines were followed for data extraction and quality assessment. The review included six studies encompassing 289 patients, presenting a comprehensive overview of pazopanib's application across different thyroid cancer subtypes. The studies reported median PFS rates ranging from 2.1 to 11.7 months and median OS rates ranging from 5.7 months to not reached. The partial response rates varied from 5% to 49%. Adverse events were common, with hypertension occurring in up to 71.7% of patients, and fatigue and diarrhea were also frequently reported. Grade 3-5 adverse events led to treatment discontinuations in up to 14% of patients. Pazopanib shows variable efficacy across thyroid cancer types, offering significant benefits in MTC and refractory DTC in terms of PFS and OS but limited impact in ATC. The adverse event profile necessitates careful management, particularly regarding hypertension and other treatment-related toxicities. Further studies are required to refine the therapeutic protocols for pazopanib, exploring combination therapies that may enhance its efficacy and reduce the adverse outcomes.

TRIM-endous functional network of tripartite motif 29 (TRIM29) in cancer progression and beyond

While most Tripartite motif (TRIM) family proteins are E3 ubiquitin ligases, some members have functions beyond the regulation of ubiquitination, impacting normal physiological processes and disease progression. TRIM29, an important member of the TRIM family, exerts a predominant influence on cancer growth, epithelial-to-mesenchymal transition, stemness and metastatic progression by directly potentiating multiple canonical oncogenic pathways. The cancer-promoting effect of TRIM29 is also evident in metabolic interventions and interference with the efficacy of cancer therapeutics. As expected for any key node in cancer, the expression of TRIM29 is tightly regulated by non-coding RNAs, epigenetic modulation, and post-translational regulation. A systematic discussion of how TRIM29 is regulated in cancer, its influences on cancer progression, and its impact on cancer therapeutics is presented in this review. We also explore the context-dependent alterations between TRIM29 function from oncogenic to tumor suppression. As TRIM29 is involved in multiple aspects of cancer progression, a better understanding of its biological impact in cancer may help improve prognosis and develop novel therapeutic combinations, leading to improved personalized cancer care.

Emerging Role of Gut Microbiota in Breast Cancer Development and Its Implications in Treatment

Background: The human digestive system contains approximately 100 trillion bacteria. The gut microbiota is an emerging field of research that is associated with specific biological processes in many diseases, including cardiovascular disease, obesity, diabetes, brain disease, rheumatoid arthritis, and cancer. Emerging evidence indicates that the gut microbiota affects the response to anticancer therapies by modulating the host immune system. Recent studies have explained a high correlation between the gut microbiota and breast cancer: dysbiosis in breast cancer may regulate the systemic inflammatory response, hormone metabolism, immune response, and the tumor microenvironment. Some of the gut bacteria are related to estrogen metabolism, which may increase or decrease the risk of breast cancer by changing the number of hormones. Further, the gut microbiota has been seen to modulate the immune system in respect of its ability to protect against and treat cancers, with a specific focus on hormone receptor-positive breast cancer. Probiotics and other therapies claiming to control the gut microbiome by bacterial means might be useful in the prevention, or even in the treatment, of breast cancer. Conclusions: The present review underlines the various aspects of gut microbiota in breast cancer risk and its clinical application, warranting research on individualized microbiome-modulated therapeutic approaches to breast cancer treatment.

Epigenetics as a strategic intervention for early diagnosis and combatting glycolyis-induced chemoresistance in gynecologic cancers

Prospective prediction from the Australian Institute of Health and Welfare (AIHW) showed a likely incidence of 1 in 23 women diagnosed with gynaecological malignancy, where the incidence of relapse with a drug-resistant clone poses a significant challenge in dealing with it even after initial treatment. Glucose metabolism has been exploited as a therapeutic target under anti-metabolomic study, but the non-specificity narrowed its applicability in cancer. Novel updates over epigenetics as a target in gynaecological cancer offer a rational idea of using this in the metabolic rewiring in mutated glycolytic flux-induced drug resistance. This review focuses on the application of epigenetic intervention at a diagnostic and therapeutic level to shift the current treatment paradigm of gynaecological cancers from reactive medicine to predictive, preventive, and personalised medicine. It presents the likely epigenetic targets that can be exploited potentially to prevent the therapeutic failure associated with glucose metabolism-induced chemotherapeutic drug resistance.

Antitumour activity of oleanolic acid: A systematic review and meta‑analysis

Oleanolic acid (OA), a compound known for its potent antitumour properties, has been the subject of investigations in both cell and animal models. Although OA has good biological activity, its low water solubility and bioavailability limit its therapeutic use, and therefore translating the potential of OA into the clinical oncology setting remains challenging. The present systematic review and meta-analysis utilized evidence from animal model studies to gain insights into the antitumour mechanisms of OA to address the gap in understanding, and to provide guidance for future research directions and potential clinical applications. The guidelines outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses were applied in the present study and a comprehensive search was conducted across the PubMed/MEDLINE, Web of Science, Cochrane Library and Embase databases, with a cut-off date of June 30, 2023. The primary focus was on randomized controlled trials that used animal models to assess the antitumour effects of OA. The methodological quality appraisal was conducted using the Systematic Review Centre for Laboratory Animal Experimentation risk of bias tool, and tumour volume and weight served as the principal outcome measures. Data were analysed using the RevMan (version 5.3) and Stata SE11 software packages, with an assessment of heterogeneity conducted using the I2 statistical test, sensitivity analysis conducted using the leave-one-out approach, and evaluation of publication bias performed using Egger's test and funnel plot analysis. The present study demonstrated a significant inhibitory effect of OA intervention on tumour growth and a decrease in tumour weight in animal models. Despite the broad spectrum of antitumour effects exhibited by OA, further investigations are warranted to optimize the dosage and administration routes of OA to maximize its efficacy in clinical cancer treatment.

Unraveling the role of long non-coding RNAs in therapeutic resistance in acute myeloid leukemia: New prospects & challenges

Acute Myeloid Leukemia (AML) is a fatal hematological disease characterized by the unchecked proliferation of immature myeloid blasts in different tissues developed by various mutations in hematopoiesis. Despite intense chemotherapeutic regimens, patients often experience poor outcomes, leading to substandard remission rates. In recent years, long non-coding RNAs (lncRNAs) have increasingly become important prognostic and therapeutic hotspots, due to their contributions to dysregulating many functional epigenetic, transcriptional, and post-translational mechanisms leading to alterations in cell expressions, resulting in increased chemoresistance and reduced apoptosis in leukemic cells. Through this review, I highlight and discuss the latest advances in understanding the major mechanisms through which lncRNAs confer therapy resistance in AML. In addition, I also provide perspective on the current strategies to target lncRNA expressions. A better knowledge of the critical role that lncRNAs play in controlling treatment outcomes in AML will help improve existing medications and devise new ones.

New Emerging Therapeutic Strategies Based on Manipulation of the Redox Regulation Against Therapy Resistance in Cancer

Background: Resistance to standard therapeutic methods, including chemotherapy, immunotherapy, and targeted therapy, remains a critical challenge in effective cancer treatment. Redox homeostasis modification has emerged as a promising approach to address medication resistance. Objective: This review aims to explore the mechanisms of redox alterations and signaling pathways contributing to treatment resistance in cancer. Methods: In this study, a comprehensive review of the molecular mechanisms underlying drug resistance governed by redox signaling was conducted. Emphasis was placed on understanding how tumor cells manage increased reactive oxygen species (ROS) levels through upregulated antioxidant systems, enabling resistance across multiple therapeutic pathways. Results: Key mechanisms identified include alterations in drug efflux, target modifications, metabolic changes, enhanced DNA damage repair, stemness preservation, and tumor microenvironment remodeling. These pathways collectively facilitate tumor cells' adaptive response and resistance to various cancer treatments. Conclusion: Developing a detailed understanding of the interrelationships between these redox-regulated mechanisms and therapeutic resistance holds potential to improve treatment effectiveness, offering valuable insights for both fundamental and clinical cancer research. Antioxid. Redox Signal. 00, 000-000.

Targeted therapies for Glioblastoma multiforme (GBM): State-of-the-art and future prospects

Glioblastoma multiforme (GBM) remains one of the most aggressive and lethal forms of brain cancer, characterized by rapid growth and resistance to conventional therapies. The present review explores the latest advancements in targeted therapies for GBM, emphasizing the critical role of the blood-brain barrier (BBB), blood-brain-tumor barrier, tumor microenvironment, and genetic mutations in influencing treatment outcomes. The impact of the key hallmarks of GBM, for example, chemoresistance, hypoxia, and the presence of glioma stem cells on the disease progression and multidrug resistance are discussed in detail. The major focus is on the innovative strategies aimed at overcoming these challenges, such as the use of monoclonal antibodies, small-molecule inhibitors, and novel drug delivery systems designed to enhance drug penetration across the BBB. Additionally, the potential of immunotherapy, specifically immune checkpoint inhibitors and vaccine-based approaches, to improve patient prognosis was explored. Recent clinical trials and preclinical studies are reviewed to provide a comprehensive overview of the current landscape and future prospects in GBM treatment. The integration of advanced computational models and personalized medicine approaches is also considered, aiming to tailor therapies to individual patient profiles for better efficacy. Overall, while significant progress has been made in understanding and targeting the complex biology of GBM, continued research and clinical innovation are imperative to develop more effective and sustainable therapeutic options for patients battling this formidable disease.

Navigating the therapeutic landscape for breast cancer: targeting breast cancer stem cells

Breast cancer is a common and deadly malignancy that affects women globally, and breast cancer stem cells (BCSCs) play an important role in tumorigenesis, development, metastasis, and recurrence. Traditional therapies often fail to eliminate BCSCs, leading to treatment resistance and relapse. This review explores the therapeutic strategies which are designed to target BCSCs, including inhibition of key signaling pathway and targeting receptor. This paper also explores the approaches to targeting BCSCs including chemotherapy, phytomedicines, and nanotechnology. Nanotechnology has gained a lot of importance in cancer therapy because of its ability to deliver therapeutic agents with more precision and minimal side effects. Various chemotherapeutic drugs, siRNAs, or gene editing tools are delivered efficiently with the use of nanocarriers which target pathways, receptors, and proteins associated with BCSCs. Over the past few years, stimuli-responsive and receptor-targeted nanocarriers have been explored for better therapeutic effects. In recent times, strategies such as chimeric antigen receptor (CAR) T-cell therapy, ablation therapy, and cell-free therapies are explored for targeting these stem cells. This review provides a recent developmental overview of strategies to attack BCSCs from conventional chemotherapeutic agents to nanotechnological platforms such as polymeric, lipidic, and metal-based nanoparticles and advanced technologies like CAR T cell therapies.

Targeting c-Met in breast cancer: From mechanisms of chemoresistance to novel therapeutic strategies

Breast cancer presents a significant challenge due to its heterogeneity and propensity for developing chemoresistance, particularly in the triple-negative subtype. c-Mesenchymal epithelial transition factor (c-Met), a receptor tyrosine kinase, presents a promising target for breast cancer therapy due to its involvement in disease progression and poor prognosis. However, the heterogeneous expression of c-Met within breast cancer subtypes and individual tumors complicates targeted therapy. Also, cancer cells can develop resistance to c-Met inhibitors through various mechanisms, including bypass signaling pathways and genetic mutations. The off-target effects of c-Met inhibitors further limit their clinical utility, necessitating the development of more selective agents. To overcome these challenges, personalized treatment approaches and combination therapies are being explored to improve treatment efficacy while minimizing adverse effects. Novel c-Met inhibitors with improved selectivity and reduced off-target toxicity show promise in preclinical studies. Additionally, targeted delivery systems aim to enhance drug localization and reduce systemic toxicity. Future directions involve refining inhibitor design and integrating c-Met inhibition into personalized treatment regimens guided by molecular profiling. This review explores the mechanisms by which c-Met contributes to chemoresistance in breast cancer and current challenges in targeting c-Met for breast cancer therapy. It discusses strategies to optimize treatment outcomes, ultimately improving patient prognosis and reducing mortality rates associated with this devastating disease.

Mitochondrial signaling pathways and their role in cancer drug resistance

Mitochondria, traditionally known as cellular powerhouses, now emerge as critical signaling centers influencing cancer progression and drug resistance. The review highlights the role that apoptotic signaling, DNA mutations, mitochondrial dynamics and metabolism play in the development of resistance mechanisms and the advancement of cancer. Targeted approaches are discussed, with an emphasis on managing mitophagy, fusion, and fission of the mitochondria to make resistant cancer cells more susceptible to traditional treatments. Additionally, metabolic reprogramming can be used to effectively target metabolic enzymes such GLUT1, HKII, PDK, and PKM2 in order to avoid resistance mechanisms. Although there are potential possibilities for therapy, the complex structure of mitochondria and their subtle role in tumor development hamper clinical translation. Novel targeted medicines are put forth, providing fresh insights on combating drug resistance in cancer. The study also emphasizes the significance of glutamine metabolism, mitochondrial respiratory complexes, and apoptotic pathways as potential targets to improve treatment effectiveness against drug-resistant cancers. Combining complementary and nanoparticle-based techniques to target mitochondria has demonstrated encouraging results in the treatment of cancer, opening doors to reduce resistance and enable individualized treatment plans catered to the unique characteristics of each patient. Suggesting innovative approaches such as drug repositioning and mitochondrial drug delivery to enhance the efficacy of mitochondria-targeting therapies, presenting a pathway for advancements in cancer treatment. This thorough investigation is a major step forward in the treatment of cancer and has the potential to influence clinical practice and enhance patient outcomes.

Beyond the Gut: The intratumoral microbiome's influence on tumorigenesis and treatment response

The intratumoral microbiome (TM) refers to the microorganisms in the tumor tissues, including bacteria, fungi, viruses, and so on, and is distinct from the gut microbiome and circulating microbiota. TM is strongly associated with tumorigenesis, progression, metastasis, and response to therapy. This paper highlights the current status of TM. Tract sources, adjacent normal tissue, circulatory system, and concomitant tumor co-metastasis are the main origin of TM. The advanced techniques in TM analysis are comprehensively summarized. Besides, TM is involved in tumor progression through several mechanisms, including DNA damage, activation of oncogenic signaling pathways (phosphoinositide 3-kinase [PI3K], signal transducer and activator of transcription [STAT], WNT/β-catenin, and extracellular regulated protein kinases [ERK]), influence of cytokines and induce inflammatory responses, and interaction with the tumor microenvironment (anti-tumor immunity, pro-tumor immunity, and microbial-derived metabolites). Moreover, promising directions of TM in tumor therapy include immunotherapy, chemotherapy, radiotherapy, the application of probiotics/prebiotics/synbiotics, fecal microbiome transplantation, engineered microbiota, phage therapy, and oncolytic virus therapy. The inherent challenges of clinical application are also summarized. This review provides a comprehensive landscape for analyzing TM, especially the TM-related mechanisms and TM-based treatment in cancer.

Personalized Versus Precision Nanomedicine for Treatment of Ovarian Cancer

The response to treatment is substantially varied between individual patients with ovarian cancer. However, chemotherapy treatment plans rarely pay sufficient attention to the mentioned factors. Instead, standardized treatment protocols are usually employed for most ovarian cancer patients. Variations in an individual's sensitivity to drugs significantly limit the effectiveness of treatment in some patients and lead to severe toxicities in others. In the present investigation, a nanotechnology-based approach for personalized treatment of ovarian carcinoma (the most lethal type of gynecological cancer) constructed on the individual genetic profile of the patient's tumor is developed and validated. The expression of predefined genes and proteins is analyzed for each patient sample. Finally, a mixture of the complex nanocarrier-based targeted delivery system containing drug(s)/siRNA(s)/targeted peptide is selected from the pre-synthesized bank and tested in vivo on murine cancer model using cancer cells isolated from tumors of each patient. Based on the results of the present study, an innovative approach and protocol for personalized treatment of ovarian cancer are suggested and evaluated. The results of the present study clearly show the advantages and perspectives of the proposed individual treatment approach.

Effect of Indigofera aspalathoides on the Expression of Inducible Nitric Oxide Synthase During 7,12-Dimethylbenz[a]anthracene-Induced Hamster Buccal Pouch Carcinogenesis

BACKGROUND

The mechanisms of inflammation and carcinogenesis are significantly influenced by nitric oxide (NO). Three different kinds of nitric oxide synthase (NOS) have been previously found: neuronal NOS, inducible nitric oxide synthase (iNOS), and endothelial NOS.

OBJECTIVES

This study looked into the properties of iNOS in hamster buccal pouch carcinogenesis caused by 7,12-dimethylbenz[a]anthracene (DMBA).

METHODS

Thirty outbred young male Syrian golden hamsters, aged six weeks, were split into five groups at random: control (n=6), administered with ethanolic extract (n=6), DMBA+EIA (ethanolic Indigofera aspalathoides) (n=6), 0.5% solution of DMBA in liquid paraffin (n=6), and DMBA alone (n=6).

RESULT

In the group treated with DMBA, the mean quantity of iNOS positive foci per section was roughly 12.2+/-4.7. The DMBA-treated pouch keratinocytes showed both nuclear and cytoplasmic stainings. Neither the mineral oil-treated nor the untreated pouches (n=10) showed any signs of iNOS activity.

CONCLUSION

In conclusion, this work has shown that hamster pouch carcinomas induced by DMBA express iNOS. This finding raises the possibility that the emergence of chemically induced oral carcinomas is linked to iNOS expression.

Long noncoding RNAs as potential targets for overcoming chemoresistance in upper gastrointestinal cancers

In the last decade, researchers have paid much attention to the role of noncoding RNA molecules in human diseases. Among the most important of these molecules are LncRNAs, which are RNA molecules with a length of more than 200 nucleotides. LncRNAs can regulate gene expression through various mechanisms, such as binding to DNA sequences and interacting with miRNAs. Studies have shown that LncRNAs may be valuable therapeutic targets in treating various cancers, including upper-gastrointestinal cancers. Upper gastrointestinal cancers, mainly referring to esophageal and gastric cancers, are among the deadliest gastrointestinal cancers. Despite notable advances, traditional chemotherapy remains a common strategy for treating these cancers. However, chemoresistance poses a significant obstacle to the effective treatment of upper gastrointestinal cancers, resulting in a low survival rate. Chemoresistance arises from various events, such as the enhancement of efflux and detoxification of chemotherapy agents, reduction of drug uptake, alteration of drug targeting, reduction of prodrug activation, strengthening of EMT and stemness, and the attenuation of apoptosis in cancerous cells. Tumor microenvironment also plays an important role in chemoresistance. Interestingly, a series of studies have revealed that LncRNAs can influence important mechanisms associated with some of the aforementioned events and may serve as promising targets for mitigating chemoresistance in upper gastrointestinal cancers. In this review paper, following a concise overview of chemoresistance mechanisms in upper gastrointestinal cancers, we will review the most intriguing findings of these investigations in detail.

Dendrimers as drug delivery systems for oncotherapy: Current status of promising applications

Cancer affects millions of people worldwide, causing death and serious health problems. Despite significant investment in the development of new anticancer compounds, there are still several limitations that can still be found. Many compounds exhibit high levels of toxicity and low bioavailability. Therefore, it is urgent to design safer, more effective, and particularly more selective compounds for oncological treatment. Dendrimers are polymeric structures that have been shown to be potential drug nanocarriers to overcome physicochemical, pharmacokinetic, and indirect pharmacodynamic issues. Due to their versatility, they can be used in the design of nanovaccines, lipophilic complexes, amphiphilic complexes, smart nanocomplexes, and others. This work targets the use of dendrimers in oncological treatment and their importance and effectiveness as drug delivery systems for the development of new therapies. For this review, only publications from the last two years are considered in this review.

Synthesis, Preclinical Toxicity, and Biodistribution of [18F]AVT-011 to Assess the P-Glycoprotein Function

Introduction: Many studies have reported the role of P-glycoprotein (Pgp) in chemoresistance in various pathological conditions such as cancer and neurodegenerative diseases, such as Alzheimer's. In this study, we are reporting the high-performance liquid chromatography (HPLC)-based purification of fluorine-18 [18F]AVT-011 and its preclinical evaluation. Methods: AVT-011 was labeled with 18F using the nucleophilic substitution method by heating the reaction mixture at 110°C for 10 min, followed by purification using preparative HPLC and C18ec cartridge. The in vitro cell uptake study was carried out in U87 cells with and without an inhibitor. The preclinical toxicity was carried out in CD1 mice in three groups, including control, AVT-011 treated, and [18F]AVT-011 treated. The biodistribution study was done in CD1 mice (n = 12) after intravenous injection of 4-6 MBq [18F]AVT-011, and mice were sacrificed at various time intervals. A dose of 3.7 ± 0.7 MBq of [18F]AVT-011 was injected intravenously in the healthy Swiss albino mice, and the whole-body micro-positron emission tomography was acquired at 0-, 30-, 60-, and 120-min postinjection. Results: The radiochemical purity of [18F]AVT-011 was 97 ± 1.5% as evaluated by radio-HPLC with a yield of 14 ± 2% and was stable up to 95% under in vitro conditions in blood and in vivo conditions up to 4 h. The in vitro cell uptake study showed a significant difference in control (27.4 ± 2.1%) and blocked U987 cells (73.2 ± 3.2%) after incubation of 120 min. The tissue distribution in mice showed the highest uptake in the liver (17.3 ± 2.4%), kidneys (16.6 ± 3.1%), lungs (10.4 ± 2.9%), and spleen (5.6 ± 0.8%) at 15 min, and the activity was washed out with time. The radioactivity cleared through the hepatorenal pathway. The animal imaging study also demonstrates a similar biodistribution pattern. Conclusions: [18F]AVT-011 showed higher specific activity than the cartridge-based method but showed similar biological activity.

Drug resistance in human cancers - Mechanisms and implications

Cancers have complex etiology and pose a significant impact from the health care perspective apart from the socio-economic implications. The enormity of challenge posed by cancers can be understood from the fact that clinical trials for cancer therapy has yielded minimum potential promises compared to those obtained for other diseases. Surgery, chemotherapy and radiotherapy continue to be the mainstay therapeutic options for cancers. Among the challenges posed by these options, induced resistance to chemotherapeutic drugs is probably the most significant contributor for poor prognosis and ineffectiveness of the therapy. Drug resistance is a property exhibited by almost all cancer types including carcinomas, leukemias, myelomas, sarcomas and lymphomas. The mechanisms by which drug resistance is induced include the factors within the tumor microenvironment, mutations in the genes responsible for drug metabolism, changes in the surface drug receptors and increased drug efflux. We present here comprehensively the drug resistance in cancers along with their mechanisms. Also, apart from resistance to regularly used chemotherapeutic drugs, we present resistance induction to new generation therapeutic agents such as monoclonal antibodies. Finally, we have discussed the experimental approaches to understand the mechanisms underlying induction of drug resistance and potential ways to mitigate induced drug resistance.

The Antitumour Mechanisms of Carotenoids: A Comprehensive Review

Carotenoids, known for their antioxidant properties, have garnered significant attention for their potential antitumour activities. This comprehensive review aims to elucidate the diverse mechanisms by which carotenoids exert antitumour effects, focusing on both well-established and novel findings. We explore their role in inducing apoptosis, inhibiting cell cycle progression and preventing metastasis by affecting oncogenic and tumour suppressor proteins. The review also explores the pro-oxidant function of carotenoids within cancer cells. In fact, although their overall contribution to cellular antioxidant defences is well known and significant, some carotenoids can exhibit pro-oxidant effects under certain conditions and are able to elevate reactive oxygen species (ROS) levels in tumoural cells, triggering mitochondrial pathways that would lead to cell death. The final balance between their antioxidant and pro-oxidant activities depends on several factors, including the specific carotenoid, its concentration and the redox environment of the cell. Clinical trials are discussed, highlighting the conflicting results of carotenoids in cancer treatment and the importance of personalized approaches. Emerging research on rare carotenoids like bacterioruberin showcases their superior antioxidant capacity and selective cytotoxicity against aggressive cancer subtypes, such as triple-negative breast cancer. Future directions include innovative delivery systems, novel combinations and personalized treatments, aiming to enhance the therapeutic potential of carotenoids. This review highlights the promising yet complex landscape of carotenoid-based cancer therapies, calling for continued research and clinical exploration.

miR-137: a potential therapeutic target for lung cancer

Lung cancer is a prevalent malignancy and the leading cause of cancer-related deaths, posing a significant threat to human health. Despite advancements in treatment, the prognosis for lung cancer patients remains poor due to late diagnosis, cancer recurrence, and drug resistance. Epigenetic research, particularly in microRNAs, has introduced a new avenue for cancer prevention and treatment. MicroRNAs, including miR-137, play a vital role in tumor development by regulating various cellular processes. MiR-137 has garnered attention for its tumor-suppressive properties, with studies showing its potential in inhibiting cancer progression. In lung cancer, miR-137 is of particular interest, with numerous reports exploring its role and mechanisms. A comprehensive review is necessary to consolidate current evidence. This review highlights recent studies on miR-137 in lung cancer, covering cell proliferation, migration, apoptosis, drug resistance, and therapy, emphasizing its potential as a biomarker and therapeutic target for lung cancer treatment and prognosis.

Chromatin remodeling-driven autophagy activation induces cisplatin resistance in oral squamous cell carcinoma

It is still challenging to predict the efficacy of cisplatin-based therapy, particularly in relation to the activation of macroautophagy/autophagy in oral squamous cell carcinoma (OSCC). We studied the effect of selected chromatin remodeling genes on the cisplatin resistance and their interplay with autophagy in 3-dimensional tumor model and xenografts. We analyzed gene expression patterns in the cisplatin-sensitive UMSCC1, and a paired cisplatin-resistant UM-Cis cells. Many histone protein gene clusters involved in nucleosome assembly showed significant difference of expression. Gain- and loss-of-function analyses revealed an inverse correlation between cisplatin resistance and HIST1H3D expression, while a positive correlation was observed with HIST3H2A or HIST3H2B expression. In UM-Cis, HIST3H2A- and HIST3H2B-mediated chromatin remodeling upregulates autophagy status, which results in cisplatin resistance. Additionally, knockdown of HIST3H2A or HIST3H2B downregulated autophagy-activating genes via chromatin compaction of their promoter regions. MiTF, one of the key autophagy regulators upregulated in UM-Cis, negatively regulated transcription of HIST1H3D, suggesting an interplay between chromatin remodeling-dependent cisplatin resistance and autophagy. On comparing the staining intensity between cisplatin-sensitive and -insensitive tissues from OSCC patients, protein expression pattern of the selected histone protein genes were matched with the in vitro data. By examining the relationship between autophagy and chromatin remodeling genes, we identified a set of candidate genes with potential use as markers predicting chemoresistance in OSCC biopsy samples.

Genetic and Epigenetic Biomarkers Associated with Early Relapse in Pediatric Acute Lymphoblastic Leukemia: A Focused Bioinformatics Study on DNA-Repair Genes

Genomic instability is one of the main drivers of tumorigenesis and the development of hematological malignancies. Cancer cells can remedy chemotherapeutic-induced DNA damage by upregulating DNA-repair genes and ultimately inducing therapy resistance. Nevertheless, the association between the DNA-repair genes, drug resistance, and disease relapse has not been well characterized in acute lymphoblastic leukemia (ALL). This study aimed to explore the role of the DNA-repair machinery and the molecular mechanisms by which it is regulated in early- and late-relapsing pediatric ALL patients. We performed secondary data analysis on the Therapeutically Applicable Research to Generate Effective Treatments (TARGET)-ALL expansion phase II trial of 198 relapsed pediatric precursor B-cell ALL. Comprehensive genetic and epigenetic investigations of 147 DNA-repair genes were conducted in the study. Gene expression was assessed using Microarray and RNA-sequencing platforms. Genomic alternations, methylation status, and miRNA transcriptome were investigated for the candidate DNA-repair genes. We identified three DNA-repair genes, ALKBH3, NHEJ1, and PARP1, that were upregulated in early relapsers compared to late relapsers (p < 0.05). Such upregulation at diagnosis was significantly associated with disease-free survival and overall survival in precursor-B-ALL (p < 0.05). Moreover, PARP1 upregulation accompanied a significant downregulation of its targeting miRNA, miR-1301-3p (p = 0.0152), which was strongly linked with poorer disease-free and overall survivals. Upregulation of DNA-repair genes, PARP1 in particular, increases the likelihood of early relapse of precursor-B-ALL in children. The observation that PARP1 was upregulated in early relapsers relative to late relapsers might serve as a valid rationale for proposing alternative treatment approaches, such as using PARP inhibitors with chemotherapy.

Sitagliptin synergizes 5-fluorouracil efficacy in colon cancer cells through MDR1-mediated flux impairment and down regulation of NFκB2 and p-AKT survival proteins

5-fluorouracil (5-FU) is an inexpensive treatment for colon cancer; however, its efficacy is limited by chemoresistance. This study investigates the combination therapy approach of 5-FU with Sitagliptin (Sita), a diabetic drug with potential cancer-modulating effects. The combination was evaluated in vitro and in silico, focusing on the effects of Sita and 5-FU on colon cancer cells. The results showed that the addition of Sita significantly decreased the IC50 of 5-FU compared to 5-Fu monotherapy. The study also found that Sita and 5-FU interact synergistically, with a combination index below 1. Sita successfully lowered the 5-FU dosage reduction index, decreasing the expression of MDR1 mRNA and p-AKT and NFκB2 subunits p100/p52 protein. Molecular docking analyses confirmed Sita's antagonistic action on MDR1 and thymidylate synthase proteins. The study concludes that sitagliptin can target MDR1, increase apoptosis, and significantly reduce the expression of p-AKT and NFκB2 cell-survival proteins. These effects sensitize colon cancer cells to 5-FU. Repurposing sitagliptin may enhance the anticancer effects of 5-FU at lower dosages.

The role of host response to chemotherapy: resistance, metastasis and clinical implications

Chemotherapy remains the primary treatment for most metastatic cancers. However, the response to chemotherapy and targeted agents is often transient, and concurrent development of resistance is the primary impediment to effective cancer therapy. Strategies to overcome resistance to treatment have focused on cancer cell intrinsic factors and the tumor microenvironment (TME). Recent evidence indicates that systemic chemotherapy has a significant impact on the host that either facilitates tumor growth, allowing metastatic spread, or renders treatment ineffective. These host responses include the release of bone marrow-derived cells, activation of stromal cells in the TME, and induction of different molecular effectors. Here, we provide an overview of chemotherapy-induced systemic host responses that support tumor aggressiveness and metastasis, and which contribute to therapy resistance. Studying host responses to chemotherapy provides a solid basis for the development of adjuvant strategies to improve treatment outcomes and delay resistance to chemotherapy. This review discusses the emerging field of host response to cancer therapy, and its preclinical and potential clinical implications, explaining how under certain circumstances, these host effects contribute to metastasis and resistance to chemotherapy.

GAS5 lncRNA: A biomarker and therapeutic target in breast cancer

Breast cancer is one of the most common causes of cancer-related mortality globally, and its aggressive phenotype results in poor treatment outcomes. Growth Arrest-Specific 5 long non-coding RNA has attracted considerable attention due to its pivotal function in apoptosis regulation and tumor aggressiveness in breast cancer. Gas5 enhances apoptosis by regulating apoptotic proteins, such as caspases and BCL2 family proteins, and the sensitivity of BCCs to chemotherapeutic agents. At the same time, low levels of GAS5 increased invasion, metastasis, and overall tumor aggressiveness. GAS5 also regulates EMT markers, critical for cancer metastasis, and influences tumor cell proliferation by regulating various signaling components. As a result, GAS5 can be restored to suppress tumor development as a possible therapeutic strategy, which might present promising prospects for a patient's treatment. Its activity levels might also be a crucial indicator and diagnostic parameter for prediction. This review highlights the significant role of GAS5 in modulating apoptosis and tumor aggressiveness in breast cancer, emphasizing its potential as a therapeutic target for breast cancer treatment and management.

Therapeutic Applications of Rosmarinic Acid in Cancer-Chemotherapy-Associated Resistance and Toxicity

Chemotherapeutic drugs and radiotherapy are fundamental treatments to combat cancer, but, often, the doses in these treatments are restricted by their non-selective toxicities, which affect healthy tissues surrounding tumors. On the other hand, drug resistance is recognized as the main cause of chemotherapeutic treatment failure. Rosmarinic acid (RA) is a polyphenol of the phenylpropanoid family that is widely distributed in plants and vegetables, including medicinal aromatic herbs, consumption of which has demonstrated beneficial activities as antioxidants and anti-inflammatories and reduced the risks of cancers. Recently, several studies have shown that RA is able to reverse cancer resistance to first-line chemotherapeutics, as well as play a protective role against toxicity induced by chemotherapy and radiotherapy, mainly due to its scavenger capacity. This review compiles information from 56 articles from Google Scholar, PubMed, and ClinicalTrials.gov aimed at addressing the role of RA as a complementary therapy in cancer treatment.

Aldo-keto reductases: Role in cancer development and theranostics

Aldo-keto reductases (AKRs) are a superfamily of enzymes that play crucial roles in various cellular processes, including the metabolism of xenobiotics, steroids, and carbohydrates. A growing body of evidence has unveiled the involvement of AKRs in the development and progression of various cancers. AKRs are aberrantly expressed in a wide range of malignant tumors. Dysregulated expression of AKRs enables the acquisition of hallmark traits of cancer by activating oncogenic signaling pathways and contributing to chemoresistance. AKRs have emerged as promising oncotherapeutic targets given their pivotal role in cancer development and progression. Inhibition of aldose reductase (AR), either alone or in combination with chemotherapeutic drugs, has evolved as a pragmatic therapeutic option for cancer. Several classes of synthetic aldo-keto reductase (AKR) inhibitors have been developed as potential anticancer agents, some of which have shown promise in clinical trials. Many AKR inhibitors from natural sources also exhibit anticancer effects. Small molecule inhibitors targeting specific AKR isoforms have shown promise in preclinical studies. These inhibitors disrupt the activation of oncogenic signaling by modulating transcription factors and kinases and sensitizing cancer cells to chemotherapy. In this review, we discuss the physiological functions of human AKRs, the aberrant expression of AKRs in malignancies, the involvement of AKRs in the acquisition of cancer hallmarks, and the role of AKRs in oncogenic signaling, and drug resistance. Finally, the potential of aldose reductase inhibitors (ARIs) as anticancer drugs is summarized.

Oncogenic Roles of UHRF1 in Cancer

Ubiquitin-like with PHD and RING finger domains 1 (UHRF1) is an essential protein involved in the maintenance of repressive epigenetic marks, ensuring epigenetic stability and fidelity. As an epigenetic regulator, UHRF1 comprises several functional domains (UBL, TTD, PHD, SRA, RING) that are collectively responsible for processes like DNA methylation, histone modification, and DNA repair. UHRF1 is a downstream effector of the RB/E2F pathway, which is nearly universally deregulated in cancer. Under physiological conditions, UHRF1 protein levels are cell cycle-dependent and are post-translationally regulated by proteasomal degradation. Conversely, UHRF1 is overexpressed and serves as an oncogenic driver in multiple cancers. This review focuses on the functional domains of UHRF1, highlighting its key interacting proteins and oncogenic roles in solid tumors including retinoblastoma, osteosarcoma, lung cancer, and breast cancer. Additionally, current therapeutic strategies targeting UHRF1 domains or its interactors are explored, providing an insight on potential clinical applications.