Regulation of Multi-drug Resistance in hepatocellular carcinoma cells is TRPC6/Calcium Dependent

Hepatocellular carcinoma drug resistance models

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. Although drug therapy has been well developed and applied, its clinical efficacy is limited due to primary or acquired drug resistance in most HCC patients. Therefore, it is of great clinical significance to elucidate the key molecular mechanisms of resistance and improve the sensitivity of HCC cells to drugs. At present, a variety of HCC drug resistance models have been developed to find out resistance mechanisms, screen biomarkers, and explore strategies to reverse drug resistance, including traditional HCC drug resistance models, HCC patient-derived drug resistance models, three-dimensional drug resistance models, transgenic drug resistance models, and multi-drug resistance models. Here, we searched PubMed, Embase and Web of science for studies related to HCC drug resistance models in recent years, systematically summarized the established methods and characteristics of these models, reviewed their applications and compared their advantages and disadvantages, aiming to provide reference for the selection of appropriate models for HCC drug resistance research.

Endolysosomal cation channel MCOLN as the novel regulator of redox homeostasis

Reactive oxygen species (ROS) production and antioxidant levels are out of equilibrium, which leads to oxidative stress. When ROS levels rise, tissues are destroyed by protein oxidation, lipid peroxidation, DNA oxidation, and mutagenesis, which activates the cell death pathway. Low levels of ROS can regulate cell survival and metabolic pathways to stimulate cell proliferation. Normal cells don't create as much ROS as cancer cells do. The endolysosomal cation channel MCOLN channels have been shown to integrate multiple processes of cell growth, division, and metabolic activities, according to recent investigations. Dysregulation of MCOLN channels activity is associated with cancer development. This review aims to discuss the current role of MCOLN channels in cancer as novel regulators of redox homeostasis, with the aim of exploiting the oncogenic potential of MCOLN channels to inspire therapeutic interventions.

Herbal Medicine: Enhancing the Anticancer Potential of Natural Products in Hepatocellular Carcinoma Therapy Through Advanced Drug Delivery Systems

Hepatocellular carcinoma (HCC) is an aggressive and prevalent liver cancer with a poor prognosis. Nanotechnology combined with natural products has emerged as a promising strategy to enhance HCC treatment efficacy. This review assesses the current literature on the application of nanotechnology in delivering natural products for HCC therapy. A comprehensive search was conducted in PubMed, Science Direct, Web of Science, and Google Scholar to identify relevant studies published up to the present articles focusing on nanotechnology-based drug delivery systems using natural products for HCC therapy, including different nanoparticle (NP) formulations and therapeutic interventions, were included. Natural products with anticancer properties have been encapsulated using various nanocarriers such as liposomes, polymeric nanoparticles, and quantum dots, which have improved drug stability, prolonged circulation time, and enhanced targeted delivery to HCC cells. These advancements have led to increased therapeutic efficacy and reduced side effects. Additionally, combining multiple natural products or integrating them with conventional therapies via nanocarriers enables personalized treatment approaches based on patient characteristics and molecular profiles. The integration of nanotechnology with natural products shows great potential for improving HCC treatment outcomes, representing a significant advancement in precision medicine for liver cancer and paving the way for more effective and personalized therapeutic strategies.

Calcium Homeostasis Disrupted-How Store-Operated Calcium Entry Factor SARAF Silencing Impacts HepG2 Liver Cancer Cells

Hepatocellular carcinoma (HCC), a highly aggressive liver malignancy, is often associated with disrupted calcium homeostasis. Store-operated calcium entry (SOCE), involving components such as STIM1, Orai1, and SARAF, plays a critical role in calcium signaling and cancer progression. While STIM1 and Orai1 have been extensively studied, SARAF's role as a negative regulator of SOCE in HCC remains poorly understood. This preliminary study investigated SARAF's effects on calcium homeostasis, proliferation, and migration in HepG2 liver cancer cells, providing initial evidence of its tumor-suppressive role. SARAF expression was modulated using siRNA knockdown and overexpression plasmids, with validation by qRT-PCR. Functional assays demonstrated that SARAF silencing increased proliferation by 50% and migration by 40% (p < 0.05), while SARAF overexpression reduced proliferation by 50% and migration by 45% (p < 0.01), highlighting its tumor-suppressive role. Intracellular calcium levels, elevated in HepG2 cells, were partially restored by SARAF overexpression, though SARAF silencing did not further disrupt calcium regulation. These findings suggest that SARAF negatively regulates proliferation and migration in HCC, potentially through its role in maintaining calcium homeostasis. SARAF represents a promising therapeutic target in HCC. Future studies should explore the downstream molecular mechanisms governing SARAF's effects, investigate its role in other cancers, and assess its clinical potential for liver cancer therapy.

Role of the nucleotide excision repair function of CETN2 in the inhibition of the sensitivity of hepatocellular carcinoma cells to oxaliplatin

Resistance to platinum-based chemotherapy agents like oxaliplatin (OXA) poses significant challenges in the treatment of cancers such as hepatocellular carcinoma (HCC). Centrin 2 (CETN2), which functions in nucleotide excision repair (NER) of DNA damage, is overexpressed in HCC. We investigated the potential role of CETN2 in modulating the sensitivity of HCC cells to OXA. CETN2 expression correlated with decreased OXA sensitivity in Huh7 and Hep3B HCC cell lines. CETN2 forms a complex with XPC, which is crucial for the initial DNA damage recognition in NER, thereby enhancing NER and reducing the efficacy of OXA. siRNA-mediated knockdown of CETN2 increased OXA-induced cytotoxicity and apoptosis, confirming its role in chemoresistance. Moreover, overexpression of CETN2 inhibited OXA-induced DNA damage, an effect partially reversed by XPC knockdown. Our findings highlight CETN2 as a potential biomarker and therapeutic target in overcoming OXA resistance in HCC and suggest the possibility for CETN2 inhibitors in enhancing chemotherapeutic efficacy in the treatment of HCC.

A quartet of cancer stem cell niches in hepatocellular carcinoma

Hepatocellular Carcinoma (HCC), the most prevalent type of primary liver cancer, is known for its aggressive behavior and poor prognosis. The Cancer Stem Cell theory, which postulates the presence of a small population of self-renewing cells called Cancer Stem Cells (CSCs), provides insights into various clinical and molecular features of HCC such as tumor heterogeneity, metabolic adaptability, therapy resistance, and recurrence. These CSCs are nurtured in the tumor microenvironment (TME), where a mix of internal and external factors creates a tumor-supportive niche that is continuously evolving both spatially and temporally, thus enhancing the tumor's complexity. This review details the origins of hepatic CSCs (HCSCs) and the factors influencing their stem-like qualities. It highlights the reciprocal crosstalk between HCSCs and the TME (hypoxic, vascular, invasive, and immune niches), exploring the signaling pathways involved and how these interactions control the malignant traits of CSCs. Additionally, it discusses potential therapeutic approaches targeting the HCSC niche and their possible uses in clinical practice.

Small molecules targeting canonical transient receptor potential channels: an update

Transient receptor potential canonical (TRPC) channels belong to an important class of non-selective cation channels. This channel family consists of multiple members that widely participate in various physiological and pathological processes. Previous studies have uncovered the intricate regulation of these channels, as well as the spatial arrangement of TRPCs and the binding sites for various small molecule compounds. Multiple small molecules have been identified as selective agonists or inhibitors targeting different subtypes of TRPC, including potential preclinical drug candidates. This review covers recent advancements in the understanding of TRPC regulation and structure and the discovery of TRPC small molecules over the past few years, with the aim of facilitating research on TRPCs and small-molecule drug discovery.

Impact of Hypoxia on Radiation-Based Therapies for Liver Cancer

Background: Hypoxia, a state of low oxygen level within a tissue, is often present in primary and secondary liver tumors. At the molecular level, the tumor cells' response to hypoxic stress induces proteomic and genomic changes which are largely regulated by proteins called hypoxia-induced factors (HIF). These proteins have been found to drive tumor progression and cause resistance to drug- and radiation-based therapies, ultimately contributing to a tumor's poor prognosis. Several imaging modalities have been developed to visualize tissue hypoxia, providing insight into a tumor's microbiology. Methods: A systematic literature search was conducted in PubMed, EMBASE, Cochrane, and Google Scholar for all reports related to hypoxia on liver tumors. All relevant studies were summarized. Results: This review will focus on the impact of hypoxia on liver tumors and review PET-, MRI-, and SPECT-based imaging modalities that have been developed to predict and assess a tumor's response to radiation therapy, with a focus on liver cancers. Conclusion: While there are numerous studies that have evaluated the impact of hypoxia on tumor outcomes, there remains a relative paucity of data evaluating and quantifying hypoxia within the liver. Novel and developing non-invasive imaging techniques able to provide functional and physiological information on tumor hypoxia within the liver may be able to assist in the treatment planning of primary and metastatic liver lesions.

LncRNA-associated competing endogenous RNA network analysis uncovered key lncRNAs involved in temozolomide resistance and tumor recurrence of glioblastoma

Temozolomide (TMZ) is a common alkylating chemotherapeutic agent used to treat brain tumors such as glioblastoma multiforme (GBM) and anaplastic astrocytoma. GBM patients develop resistance to this drug, which has an unclear and complicated molecular mechanism. The competing endogenous RNAs (ceRNAs) play critical roles in tumorigenesis, drug resistance, and tumor recurrence in cancers. This study aims to predict ceRNAs, their possible involvement, and underlying molecular mechanisms in TMZ resistance. Therefore, we analyzed coding and non-coding RNA expression levels in TMZ-resistant GBM samples compared to sensitive GBM samples and performed pathway analysis of mRNAs differentially expressed (DE) in TMZ-resistant samples. We next applied a mathematical model on 950 DE long non-coding RNAs (lncRNAs), 116 microRNAs (miRNAs), and 7977 mRNAs and obtained 10 lncRNA-associated ceRNAs that may be regulating potential target genes involved in cancer-related pathways by sponging 25 miRNAs in TMZ-resistant GBM. Among these, two lncRNAs named ARFRP1 and RUSC2 regulate five target genes (IRS1, FOXG1, GNG2, RUNX2, and CACNA1E) involved in AMPK, AKT, mTOR, and TGF-β signaling pathways that activate or inhibit autophagy causing TMZ resistance. The novel lncRNA-associated ceRNA network predicted in GBM offers a fresh viewpoint on TMZ resistance, which might contribute to treating this malignancy.

Ion channels and their role in chemo-resistance

Ion channels play a crucial role in cellular signaling, homeostasis, and generation of electrical and chemical signals. Aberrant expression and dysregulation of ion channels have been associated with cancer development and resistance to conventional cancer treatment such as chemotherapy. Several molecular mechanisms have been proposed to explain this phenomenon. Including evasion of apoptosis, decreased drug accumulation in cancer cells, detoxifying and activation of alternative escape pathways such as autophagy. Each of these mechanisms leads to a reduction of the therapeutic efficacy of administered drugs, causing more difficulty in cancer treatment. This review highlights the linkages between ion channels and resistance to chemotherapy. Furthermore, it elaborates their molecular mechanisms and the potential of being therapeutic targets in clinical management.

Role of TRP Channels in Liver-Related Diseases

The liver plays a crucial role in preserving the homeostasis of an entire organism by metabolizing both endogenous and exogenous substances, a process that relies on the harmonious interactions of hepatocytes, hepatic stellate cells (HSCs), Kupffer cells (KCs), and vascular endothelial cells (ECs). The disruption of the liver's normal structure and function by diverse pathogenic factors imposes a significant healthcare burden. At present, most of the treatments for liver disease are palliative in nature, rather than curative or restorative. Transient receptor potential (TRP) channels, which are extensively expressed in the liver, play a crucial role in regulating intracellular cation concentration and serve as the origin or intermediary stage of certain signaling pathways that contribute to liver diseases. This review provides an overview of recent developments in liver disease research, as well as an examination of the expression and function of TRP channels in various liver cell types. Furthermore, we elucidate the molecular mechanism by which TRP channels mediate liver injury, liver fibrosis, and hepatocellular carcinoma (HCC). Ultimately, the present discourse delves into the current state of research and extant issues pertaining to the targeting of TRP channels in the treatment of liver diseases and other ailments. Despite the numerous obstacles encountered, TRP channels persist as an extremely important target for forthcoming clinical interventions aimed at treating liver diseases.

Doxorubicin resistance in breast cancer is mediated via the activation of FABP5/PPARγ and CaMKII signaling pathway

Breast cancer is the most prevalent malignancy among women. Doxorubicin (Dox) resistance was one of the major obstacles to improving the clinical outcome of breast cancer patients. The purpose of this study was to investigate the relationship between the FABP signaling pathway and Dox resistance in breast cancer. The resistance property of MCF-7/ADR cells was evaluated employing CCK-8, Western blot (WB), and confocal microscopy techniques. The glycolipid metabolic properties of MCF-7 and MCF-7/ADR cells were identified using transmission electron microscopy, PAS, and Oil Red O staining. FABP5 and CaMKII expression levels were assessed through GEO and WB approaches. The intracellular calcium level was determined by flow cytometry. Clinical breast cancer patient's tumor tissues were evaluated by immunohistochemistry to determine FABP5 and p-CaMKII protein expression. In the presence or absence of FABP5 siRNA or the FABP5-specific inhibitor SBFI-26, Dox resistance was investigated utilizing CCK-8, WB, and colony formation methods, and intracellular calcium level was examined. The binding ability of Dox was explored by molecular docking analysis. The results indicated that the MCF-7/ADR cells we employed were Dox-resistant MCF-7 cells. FABP5 expression was considerably elevated in MCF-7/ADR cells compared to parent MCF-7 cells. FABP5 and p-CaMKII expression were increased in resistant patients than in sensitive individuals. Inhibition of the protein expression of FABP5 by siRNA or inhibitor increased Dox sensitivity in MCF-7/ADR cells and lowered intracellular calcium, PPARγ, and autophagy. Molecular docking results showed that FABP5 binds more powerfully to Dox than the known drug resistance-associated protein P-GP. In summary, the PPARγ and CaMKII axis mediated by FABP5 plays a crucial role in breast cancer chemoresistance. FABP5 is a potentially targetable protein and therapeutic biomarker for the treatment of Dox resistance in breast cancer.

Targeting liver cancer stem cell through EpCAM therapy targeted with chemotherapy endorse enhanced progression in hepatocellular carcinoma

Background

Two chief hurdles in most cancer treatments are chemoresistance and tumor recurrence, especially counting hepatocellular carcinoma (HCC). Most conformist chemotherapy fails to completely cure HCC patients because of its susceptibility to develop multidrug resistance (MDR) through factors such as hypoxia, cancer stem cells, and drug efflux mechanism cancer stem cells (CSC) which are significant factors involved in chemoresistance. It has been exposed that targeting liver cancer stem cells and chemotherapeutic drugs have a better selected, overall survival rate for hepatocellular carcinoma patients.

Aim

This study aims to investigate the effectiveness of targeting stem cells for liver cancer using a therapy that targets EpCAM in combination with chemotherapy and how this approach can enhance the treatment outcomes in hepatocellular carcinoma, the most prevalent kind of liver cancer.

Results

The outcome was studied by flow cytometry, Western blot, RT-PCR, and cytotoxicity assays. EpCAM gene silenced and XAV939-treated cells showed decreased expression of CD133, a liver cancer stem cell (LCSC) marker in flow cytometry analysis, and reduced expression of ABCG2 gene, which is a reliable marker for chemoresistance in RT-PCR and western blot analysis; it was also unable to form colonies in colony forming assay. Similarly, in the spheroid formation assay, EpCAM gene silenced cells and XAV939-treated cells in combinations with cisplatin treatment were powerless to appear spheroid, whereas cisplatin alone-treated cells showed spheroids. In the cytotoxicity assay, cisplatin alone and combined with EpCAM silenced and XAV939-treated cells showed more lactate dehydrogenase (LDH) release than EpCAM silenced arm XAV939 treated components.

Conclusion

These findings confirm our hypothesis that conventional chemotherapy kills cancer cells but not cancer stem cells. We believe EpCAM-targeted therapy enhances chemosensitivity and decreases relapsed chances. This approach might be the best option for a better prognosis for hepatocellular carcinoma patients.

Transient Receptor Potential Canonical 6 (TRPC6) Channel in the Pathogenesis of Diseases: A Jack of Many Trades

The mammalian Transient Receptor Potential Canonical (TRPC) subfamily comprises seven transmembrane proteins (TRPC1-7) forming cation channels in the plasma membrane of mammalian cells. TRPC channels mediate Ca²⁺ and Na⁺ influx into the cells. Amongst TRPCs, TRPC6 deficiency or increased activity due to gain-of-function mutations has been associated with a multitude of diseases, such as kidney disease, pulmonary disease, and neurological disease. Indeed, the TRPC6 protein is expressed in various organs and is involved in diverse signalling pathways. The last decade saw a surge in the investigative studies concerning the physiological roles of TRPC6 and describing the development of new pharmacological tools modulating TRPC6 activity. The current review summarizes the progress achieved in those investigations.

Intersection between calcium signalling and epithelial-mesenchymal plasticity in the context of cancer

Epithelial-mesenchymal transition (EMT) is a form of cellular phenotypic plasticity and is considered a crucial step in the progression of many cancers. The calcium ion (Ca²⁺) acts as a ubiquitous second messenger and is implicated in many cellular processes, including cell death, migration, invasion and more recently EMT. Throughout this review, the complex interplay between Ca²⁺ signalling and EMT will be explored. An overview of the Ca²⁺ pathways that are remodelled as a consequence of EMT is provided and the role of Ca²⁺ signalling in regulating EMT and its significance is considered. Ca²⁺ signalling pathways may represent a therapeutic opportunity to regulate EMT. However, as will be described in this review, the complexity of these signalling pathways represents significant challenges that must be considered if Ca²⁺ signalling is to be manipulated with the aim of therapeutic intervention in cancer.

The role of transient receptor potential channels in metastasis

Metastasis is the hallmark of failed tumor treatment and is typically associated with death due to cancer. Transient receptor potential (TRP) channels affect changes in intracellular calcium concentrations and participate at every stage of metastasis. Further, they increase the migratory ability of tumor cells, promote angiogenesis, regulate immune function, and promote the growth of tumor cells through changes in gene expression and function. In this review, we explore the potential mechanisms of action of TRP channels, summarize their role in tumor metastasis, compile inhibitors of TRP channels relevant in tumors, and discuss current challenges in research on TRP channels involved in tumor metastasis.

Targeted Therapy and Personalized Medicine

Targeted therapy and personalized medicine are novel emerging disciplines of cancer research intended for treatment and prevention. One of the most significant advancements in modern oncology is the shift from an organ-centric strategy to a personalized strategy guided by deep molecular analysis. This shift in view, which focuses on the tumour's precise molecular changes, has paved the way for individualized treatment. Researchers and clinicians are using targeted therapies to select the best treatment available based on the molecular characterization of malignant cancer. In the treatment of a cancer, personalized medicine entails the use of genetic, immunological, and proteomic profiling to provide therapeutic alternatives as well as prognostic information about cancer. In this book, targeted therapies and personalized medicine have been covered for specific malignancies, including latest FDA-approved targeted therapies and it also sheds light on effective anti-cancer regimens and drug resistance. This will help to enhance our ability to conduct individualized health planning, make early diagnoses, and choose optimal medications for each cancer patient with predictable side effects and outcomes in a quickly evolving era. Various applications and tools' capacity have been improved for early diagnosis of cancer and the growing number of clinical trials that choose specific molecular targets reflects this predicament. Nevertheless, there are several limitations that must need to be addressed. Hence, in this chapter, we will discuss recent advancements, challenges, and opportunities in personalized medicine for various cancers, with a specific emphasis on target therapies in diagnostics and therapeutics.

Calcium signaling: A therapeutic target to overcome resistance to therapies in cancer

Innate and acquired resistances to therapeutic agents are responsible for the failure of cancer treatments. Due to the multifactorial nature of resistance, the identification of new therapeutic targets is required to improve cancer treatment. Calcium is a universal second messenger that regulates many cellular functions such as proliferation, migration, and survival. Calcium channels, pumps and exchangers tightly regulate the duration, location and magnitude of calcium signals. Many studies have implicated dysregulation of calcium signaling in several pathologies, including cancer. Abnormal calcium fluxes due to altered channel expression or activation contribute to carcinogenesis and promote tumor development. However, there is limited information on the role of calcium signaling in cancer resistance to therapeutic drugs. This review discusses the role of calcium signaling as a mediator of cancer resistance, and assesses the potential value of combining anticancer therapy with calcium signaling modulators to improve the effectiveness of current treatments.

Blocked metabotropic glutamate receptor 5 enhances chemosensitivity in hepatocellular carcinoma and attenuates chemotoxicity in the normal liver by regulating DNA damage

DNA damaging agents are used as chemotherapeutics in many cancers, including hepatocellular carcinoma (HCC). However, they are associated with problems such as low sensitivity to chemotherapy and the induction of liver injury, underscoring the need to identify new therapies. Here, we investigated the differential regulatory effect of metabotropic glutamate receptor 5 (mGlu5) on chemosensitivity in HCC and chemotoxicity to the normal liver. The expression of mGlu5 was higher in HCC than in the normal liver, and correlated with poor prognosis according to The Cancer Genome Atlas database and Integrative Molecular Database of Hepatocellular Carcinoma. Cisplatin, oxaliplatin or methyl methanesulfonate (MMS) caused cell death by decreasing mGlu5 expression in HCC cells and increased mGlu5 expression in hepatic cells. In HCC cells, inhibition of mGlu5 aggravated MMS-induced DNA damage by increasing intracellular Ca2+ overload and mitogen-activated protein kinase (MAPK) activation, thereby promoting cell death, and activation of mGlu5 rescued the effect of MMS. However, in hepatic cells, mGlu5 inhibition alleviated MMS-induced DNA damage by downregulating Ca2+-derived MAPK pathways to advance hepatic cell survival. The opposite effects of mGlu5 overexpression or knockdown on MMS-induced DNA damage supported that cell death is a result of the differential regulation of mGlu5 expression. Inhibition of mGlu5 increased chemosensitivity and decreased chemotoxicity in a rat tumor model. This study suggests that mGlu5 inhibition could act synergistically with HCC chemotherapeutics with minimal side effects, which may improve the treatment of patients with HCC in the future.

Effects of Ion-Transporting Proteins on the Digestive System Under Hypoxia

Hypoxia refers to a state of oxygen limitation, which mainly mediates pathological processes in the human body and participates in the regulation of normal physiological processes. In the hypoxic environment, the main regulator of human body homeostasis is the hypoxia-inducible factor family (HIF). HIF can regulate the expression of many hypoxia-induced genes and then participate in various physiological and pathological processes of the human body. Ion-transporting proteins are extremely important types of proteins. Ion-transporting proteins are distributed on cell membranes or organelles and strictly control the inflow or outflow of ions in cells or organelles. Changes in ions in cells are often closely related to extensive physiological and pathological processes in the human body. Numerous studies have confirmed that hypoxia and its regulatory factors can regulate the transcription and expression of ion-transporting protein-related genes. Under hypoxic stress, the regulation and interaction of ion-transporting proteins by hypoxia often leads to diseases of various human systems and even tumors. Using ion-transporting proteins and hypoxia as targets to explore the mechanism of digestive system diseases and targeted therapy is expected to become a new breakthrough point.

The modulation of ion channels in cancer chemo-resistance

Ion channels modulate the flow of ions into and out of a cell or intracellular organelle, leading to generation of electrical or chemical signals and regulating ion homeostasis. The abundance of ion channels in the plasma and intracellular membranes are subject to physiological and pathological regulations. Abnormal and dysregulated expressions of many ion channels are found to be linked to cancer and cancer chemo-resistance. Here, we will summarize ion channels distribution in multiple tumors. And the involvement of ion channels in cancer chemo-resistance will be highlighted.

Ca2+ Signalling and Hypoxia/Acidic Tumour Microenvironment Interplay in Tumour Progression

Solid tumours are characterised by an altered microenvironment (TME) from the physicochemical point of view, displaying a highly hypoxic and acidic interstitial fluid. Hypoxia results from uncontrolled proliferation, aberrant vascularization and altered cancer cell metabolism. Tumour cellular apparatus adapts to hypoxia by altering its metabolism and behaviour, increasing its migratory and metastatic abilities by the acquisition of a mesenchymal phenotype and selection of aggressive tumour cell clones. Extracellular acidosis is considered a cancer hallmark, acting as a driver of cancer aggressiveness by promoting tumour metastasis and chemoresistance via the selection of more aggressive cell phenotypes, although the underlying mechanism is still not clear. In this context, Ca2+ channels represent good target candidates due to their ability to integrate signals from the TME. Ca2+ channels are pH and hypoxia sensors and alterations in Ca2+ homeostasis in cancer progression and vascularization have been extensively reported. In the present review, we present an up-to-date and critical view on Ca2+ permeable ion channels, with a major focus on TRPs, SOCs and PIEZO channels, which are modulated by tumour hypoxia and acidosis, as well as the consequent role of the altered Ca2+ signals on cancer progression hallmarks. We believe that a deeper comprehension of the Ca2+ signalling and acidic pH/hypoxia interplay will break new ground for the discovery of alternative and attractive therapeutic targets.

TRPC6 interacted with KCa1.1 channels to regulate the proliferation and apoptosis of glioma cells

Malignant glioma is the most aggressive and deadliest brain malignancy. TRPC6 and K_Ca1.1, two ion channels, have been considered as potential therapeutic targets for malignant glioma treatment. TRPC6, a Ca²⁺-permeable channel, plays a vital role in promoting tumorigenesis and the progression of glioma. K_Ca1.1, a large-conductance Ca²⁺-activated channel, is also involved in growth and migration of glioma. However, the underlying mechanism by which these two ion channels promote glioma progression was unclear. In our study, we found that TRPC6 upregulated the expression of K_Ca1.1, while the immunoprecipitation analysis also showed that TRPC6 interacts with K_Ca1.1 channels in glioma cells. The currents of K_Ca1.1 recorded by the whole-cell patch clamp technique were increased by TRPC6 in glioma cells, suggesting that TRPC6 can provide a Ca²⁺ source for the activation of K_Ca1.1 channels. It was also suggested that TRPC6 regulates the proliferation and apoptosis of glioma cells through K_Ca1.1 channels in vitro. Therefore, C6-bearing glioma rats were established to validate the results in vitro. After the administration of paxilline (a specific inhibitor of K_Ca1.1 channels), TRPC6-dependent growth of glioma was inhibited in vivo. We also found that TRPC6 enhanced co-expression with K_Ca1.1 in glioma. These all suggested that TRPC6/K_Ca1.1 signal plays a role in promoting the growth of glioma. Our results provided new evidence for TRPC6 and K_Ca1.1 as potential targets for glioma treatment.

Ca2+ Transportome and the Interorganelle Communication in Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is a type of liver cancer with a poor prognosis for survival given the complications it bears on the patient. Though damages to the liver are acknowledged prodromic factors, the precise molecular aetiology remains ill-defined. However, many genes coding for proteins involved in calcium (Ca²⁺) homeostasis emerge as either mutated or deregulated. Ca²⁺ is a versatile signalling messenger that regulates functions that prime and drive oncogenesis, favouring metabolic reprogramming and gene expression. Ca²⁺ is present in cell compartments, between which it is trafficked through a network of transporters and exchangers, known as the Ca²⁺ transportome. The latter regulates and controls Ca²⁺ dynamics and tonicity. In HCC, the deregulation of the Ca²⁺ transportome contributes to tumorigenesis, the formation of metastasizing cells, and evasion of cell death. In this review, we reflect on these aspects by summarizing the current knowledge of the Ca²⁺ transportome and overviewing its composition in the plasma membrane, endoplasmic reticulum, and the mitochondria.

Ion Channel Involvement in Tumor Drug Resistance

Over 90% of deaths in cancer patients are attributed to tumor drug resistance. Resistance to therapeutic agents can be due to an innate property of cancer cells or can be acquired during chemotherapy. In recent years, it has become increasingly clear that regulation of membrane ion channels is an important mechanism in the development of chemoresistance. Here, we review the contribution of ion channels in drug resistance of various types of cancers, evaluating their potential in clinical management. Several molecular mechanisms have been proposed, including evasion of apoptosis, cell cycle arrest, decreased drug accumulation in cancer cells, and activation of alternative escape pathways such as autophagy. Each of these mechanisms leads to a reduction of the therapeutic efficacy of administered drugs, causing more difficulty in cancer treatment. Thus, targeting ion channels might represent a good option for adjuvant therapies in order to counteract chemoresistance development.

Targeting Ca2+ signaling: A new arsenal against cancer

The drug resistance of cancer cells is a major concern in medical oncology, resulting in the failure of chemotherapy. Ca²⁺ plays a pivotal role in inducing multidrug resistance in cancer cells. Calcium signaling is a critical regulator of many cancer hallmarks, such as angiogenesis, invasiveness, and migration. In this review, we describe the involvement of Ca²⁺ signaling and associated proteins in cancer progression and in the development of multidrug resistance in cancer cells. We also highlight the possibilities and challenges of targeting the Ca²⁺ channels, transporters, and pumps involved in Ca²⁺ signaling in cancer cells through structure-based drug design. This work will open a new therapeutic window to be used against cancer in upcoming years.

Transient Receptor Potential Channels in the Epithelial-to-Mesenchymal Transition

The epithelial-to-mesenchymal transition (EMT) is a strictly regulated process that is indispensable for normal development, but it can result in fibrosis and cancer progression. It encompasses a complete alteration of the cellular transcriptomic profile, promoting the expression of genes involved in cellular migration, invasion and proliferation. Extracellular signaling factors driving the EMT process require secondary messengers to convey their effects to their targets. Due to its remarkable properties, calcium represents an ideal candidate to translate molecular messages from receptor to effector. Therefore, calcium-permeable ion channels that facilitate the influx of extracellular calcium into the cytosol can exert major influences on cellular phenotype. Transient receptor potential (TRP) channels represent a superfamily of non-selective cation channels that decode physical and chemical stimuli into cellular behavior. Their role as cellular sensors renders them interesting proteins to study in the context of phenotypic transitions, such as EMT. In this review, we elaborate on the current knowledge regarding TRP channel expression and activity in cellular phenotype and EMT.

Understanding doxorubicin associated calcium remodeling during triple-negative breast cancer treatment: an in silico study

Aim:

Triple-negative breast cancer (TNBC) is the most malignant subtype of breast cancer with high heterogeneity, rapid progression, and paucity of treatment options. The most effective chemotherapeutic drug used to treat TNBC is doxorubicin (Doxo) which is an anthracycline antibiotic. However, Doxo treatment alters cytosolic calcium dynamics leading to drug-resistance condition. The aim of this study is to capture the alterations in the activity of various calcium channels and pumps during Doxo treatment and their consequences on cytosolic calcium dynamics that ultimately result in drug resistance.

Methods:

In the present study, a mathematical model is proposed to capture the complex dynamical landscape of intracellular calcium during Doxo treatment. This study provides an insight into Doxo remodeling of calcium dynamics and associated drug-resistance effect. The model was first analyzed analytically and then explored through numerical simulation using techniques like global sensitivity analysis, parameter recalibration, etc.

Results:

The model is used to predict the potential combination therapy for Doxo that can overcome Doxo associated drug resistance. The results show targeting the dysregulated Ca²⁺ channels and pumps might provide efficient chemotherapy in TNBC. It was also observed that the indispensability of calcium influx rate is paramount in the Doxo drug resistance. Finally, three drugs were identified from existing literature that could be used as a combination therapy along with Doxo.

Conclusions:

The investigation highlights the importance of integrating the calcium signaling of various calcium regulating compounds for their effective anti-tumor effects deliverance along with chemotherapeutic agents. The results from this study might provide a new direction to the experimental biologists to explore different combination therapies with Doxo to enhance its anti-tumor effect.

Canonical transient receptor potential channels and their modulators: biology, pharmacology and therapeutic potentials

Canonical transient receptor potential channels (TRPCs) are nonselective, high calcium permeability cationic channels. The TRPCs family includes TRPC1, TRPC2, TRPC3, TRPC4, TRPC5, TRPC6, and TRPC7. These channels are widely expressed in the cardiovascular and nervous systems and exist in many other human tissues and cell types, playing several crucial roles in the human physiological and pathological processes. Hence, the emergence of TRPCs modulators can help investigate these channels’ applications in health and disease. It is worth noting that the TRPCs subfamilies have structural and functional similarities, which presents a significant difficulty in screening and discovering of TRPCs modulators. In the past few years, only a limited number of selective modulators of TRPCs were detected; thus, additional research on more potent and more selective TRPCs modulators is needed. The present review focuses on the striking desired therapeutic effects of TRPCs modulators, which provides intel on the structural modification of TRPCs modulators and further pharmacological research. Importantly, TRPCs modulators can significantly facilitate future studies of TRPCs and TRPCs related diseases.

Revealing the Potential Application of EC-Synthetic Retinoid Analogues in Anticancer Therapy

(1) Background and Aim: All-trans retinoic acid (ATRA) induces differentiation and inhibits growth of many cancer cells. However, resistance develops rapidly prompting the urgent need for new synthetic and potent derivatives. EC19 and EC23 are two synthetic retinoids with potent stem cell neuro-differentiation activity. Here, these compounds were screened for their in vitro antiproliferative and cytotoxic activity using an array of different cancer cell lines. (2) Methods: MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, AV/PI (annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI)), cell cycle analysis, immunocytochemistry, gene expression analysis, Western blotting, measurement of glutamate and total antioxidant concentrations were recruited. (3) Results: HepG2, Caco-2, and MCF-7 were the most sensitive cell lines; HepG2 (ATRA; 36.2, EC19; 42.2 and EC23; 0.74 µM), Caco-2 (ATRA; 58.0, EC19; 10.8 and EC23; 14.7 µM) and MCF-7 (ATRA; 99.0, EC19; 9.4 and EC23; 5.56 µM). Caco-2 cells were selected for further biochemical investigations. Isobologram analysis revealed the combined synergistic effects with 5-fluorouracil with substantial reduction in IC50. All retinoids induced apoptosis but EC19 had higher potency, with significant cell cycle arrest at subG0-G1, -S and G2/M phases, than ATRA and EC23. Moreover, EC19 reduced cellular metastasis in a transwell invasion assay due to overexpression of E-cadherin, retinoic acid-induced 2 (RAI2) and Werner (WRN) genes. (4) Conclusion: The present study suggests that EC-synthetic retinoids, particularly EC19, can be effective, alone or in combinations, for potential anticancer activity to colorectal cancer. Further in vivo studies are recommended to pave the way for clinical applications.

The Role of Calcium Signaling in Regulation of Epithelial-Mesenchymal Transition

Despite substantial advances in the field of cancer therapeutics, metastasis is a significant challenge for a favorable clinical outcome. Epithelial to mesenchymal transition (EMT) is a process of acquiring increased motility, invasiveness, and therapeutic resistance by cancer cells for their sustained growth and survival. A plethora of intrinsic mechanisms and extrinsic microenvironmental factors drive the process of cancer metastasis. Calcium (Ca2+) signaling plays a critical role in dictating the adaptive metastatic cell behavior comprising of cell migration, invasion, angiogenesis, and intravasation. By modulating EMT, Ca2+ signaling can regulate the complexity and dynamics of events leading to metastasis. This review summarizes the role of Ca2+ signal remodeling in the regulation of EMT and metastasis in cancer.

Progress in Natural Compounds/siRNA Co-delivery Employing Nanovehicles for Cancer Therapy

Chemotherapy using natural compounds, such as resveratrol, curcumin, paclitaxel, docetaxel, etoposide, doxorubicin, and camptothecin, is of importance in cancer therapy because of the outstanding therapeutic activity and multitargeting capability of these compounds. However, poor solubility and bioavailability of natural compounds have limited their efficacy in cancer therapy. To circumvent this hurdle, nanocarriers have been designed to improve the antitumor activity of the aforementioned compounds. Nevertheless, cancer treatment is still a challenge, demanding novel strategies. It is well-known that a combination of natural products and gene therapy is advantageous over monotherapy. Delivery of multiple therapeutic agents/small interfering RNA (siRNA) as a potent gene-editing tool in cancer therapy can maximize the synergistic effects against tumor cells. In the present review, co-delivery of natural compounds/siRNA using nanovehicles are highlighted to provide a backdrop for future research.

Synergism of cisplatin-oleanolic acid co-loaded hybrid nanoparticles on gastric carcinoma cells for enhanced apoptosis and reversed multidrug resistance

Combined administration of different drugs is a widely acknowledged approach for effective cancer therapy. However, the limited targeting, as well as inferior drug loading capacities of current drug delivery systems (DDS), are still the bottleneck for better performance in cancer treatment. Herein, we successfully developed a cancer cell membrane (CM) decorated calcium carbonate (CC) hybrid nanoparticles (HN) for the co-delivery of cisplatin (CDDP) and oleanolic acid (OA). The physicochemical property of HN/CDDP/OA was evaluated, which revealed that the as-prepared DDS was core-shell structured and well-dispersed nanoparticles with size around 100 nm. The HN/CDDP/OA showed high stability and biocompatibility with pH-responsive drug release. Moreover, the CM modification in HN also demonstrated highly elevated tumor-homing nature than bare CC. Finally, the feasibility of HN/CDDP/OA in the treatment of gastric cancer (MGC-803 cell line) was assessed. HN/CDDP/OA showed better performance than mono systems with enhanced apoptosis and capable of reversing multidrug resistance (MDR) of cancer cells.

Targeting the Calcium Signalling Machinery in Cancer

Cancer is caused by excessive cell proliferation and a propensity to avoid cell death, while the spread of cancer is facilitated by enhanced cellular migration, invasion, and vascularization. Cytosolic Ca²⁺ is central to each of these important processes, yet to date, there are no cancer drugs currently being used clinically, and very few undergoing clinical trials, that target the Ca²⁺ signalling machinery. The aim of this review is to highlight some of the emerging evidence that targeting key components of the Ca²⁺ signalling machinery represents a novel and relatively untapped therapeutic strategy for the treatment of cancer.

LncRNA CRNDE facilitates epigenetic suppression of CELF2 and LATS2 to promote proliferation, migration and chemoresistance in hepatocellular carcinoma

Our study aimed to investigate the expression, functional significance, and related mechanism of long noncoding RNA CRNDE (colorectal neoplasia differentially expressed) in hepatocellular carcinoma (HCC) pathogenesis. The resulted revealed that CRNDE was significantly overexpressed in HCC tissues and cell lines, and was statistically correlated with poor clinical outcome. CRNDE knockdown markedly decreased HCC cell proliferation, migration, and chemoresistance. In addition, in vivo experiments confirmed the suppressive effect of CRNDE knockdown on HCC progression. Mechanically, CRNDE directly bound to EZH2 (enhancer of zeste homolog), SUZ12 (suppressor of zeste 12), SUV39H1, and mediated their inhibition of tumor suppressor genes, including CUGBP Elav-like family member 2 (CELF2) and large tumor suppressor 2 (LATS2). CELF2 exerted tumor suppressive effect in HCC and was involved in CRNDE-mediated oncogenic effect. In addition, the oncogenic effects of CRNDE on HCC proliferation, migration and tumorigenesis, as well as its inhibition of Hippo pathway were abolished by LATS2 overexpression. Together, our work demonstrated the importance of CRNDE in HCC progression and elucidated the underlying molecular mechanisms. These findings provided new insights into HCC pathogenesis and chemoresistance mediated by CRNDE.

Calcium Permeable Channels in Cancer Hallmarks

Cancer, the second cause of death worldwide, is characterized by several common criteria, known as the “cancer hallmarks” such as unrestrained cell proliferation, cell death resistance, angiogenesis, invasion and metastasis. Calcium permeable channels are proteins present in external and internal biological membranes, diffusing Ca²⁺ ions down their electrochemical gradient. Numerous physiological functions are mediated by calcium channels, ranging from intracellular calcium homeostasis to sensory transduction. Consequently, calcium channels play important roles in human physiology and it is not a surprise the increasing number of evidences connecting calcium channels disorders with tumor cells growth, survival and migration. Multiple studies suggest that calcium signals are augmented in various cancer cell types, contributing to cancer hallmarks. This review focuses in the role of calcium permeable channels signaling in cancer with special attention to the mechanisms behind the remodeling of the calcium signals. Transient Receptor Potential (TRP) channels and Store Operated Channels (SOC) are the main extracellular Ca²⁺ source in the plasma membrane of non-excitable cells, while inositol trisphosphate receptors (IP₃R) are the main channels releasing Ca²⁺ from the endoplasmic reticulum (ER). Alterations in the function and/or expression of these calcium channels, as wells as, the calcium buffering by mitochondria affect intracellular calcium homeostasis and signaling, contributing to the transformation of normal cells into their tumor counterparts. Several compounds reported to counteract several cancer hallmarks also modulate the activity and/or the expression of these channels including non-steroidal anti-inflammatory drugs (NSAIDs) like sulindac and aspirin, and inhibitors of polyamine biosynthesis, like difluoromethylornithine (DFMO). The possible role of the calcium permeable channels targeted by these compounds in cancer and their action mechanism will be discussed also in the review.

Exploring the Therapeutic Potential of Membrane Transport Proteins: Focus on Cancer and Chemoresistance

Improving the therapeutic efficacy of conventional anticancer drugs represents the best hope for cancer treatment. However, the shortage of druggable targets and the increasing development of anticancer drug resistance remain significant problems. Recently, membrane transport proteins have emerged as novel therapeutic targets for cancer treatment. These proteins are essential for a plethora of cell functions ranging from cell homeostasis to clinical drug toxicity. Furthermore, their association with carcinogenesis and chemoresistance has opened new vistas for pharmacology-based cancer research. This review provides a comprehensive update of our current knowledge on the functional expression profile of membrane transport proteins in cancer and chemoresistant tumours that may form the basis for new cancer treatment strategies.

Deletion of the Golgi Ca2+-ATPase PMR1 gene potentiates antifungal effects of dodecanol that depend on intracellular Ca2+ accumulation in budding yeast

One strategy for overcoming infectious diseases caused by drug-resistant fungi involves combining drugs rendered inactive by resistance with agents targeting the drug resistance mechanism. The antifungal activity of n-dodecanol disappears as incubation time passes. In Saccharomyces cerevisiae, anethole, a principal component of anise oil, prolongs the transient antifungal effect of dodecanol by downregulating genes of multidrug efflux pumps, mainly PDR5. However, the detailed mechanisms of dodecanol's antifungal action and the anethole-induced prolonged antifungal action of dodecanol are unknown. Screening of S. cerevisiae strains lacking genes related to Ca2+ homeostasis and signaling identified a pmr1Δ strain lacking Golgi Ca2+-ATPase as more sensitive to dodecanol than the parental strain. Dodecanol and the dodecanol + anethole combination significantly increased intracellular Ca2+ levels in both strains, but the mutant failed to clear intracellular Ca2+ accumulation. Further, dodecanol and the drug combination reduced PMR1 expression and did not lead to specific localization of Pmr1p in the parental strain after 4-h treatment. By contrast with the parental strain, dodecanol did not stimulate PDR5 expression in pmr1Δ. Based on these observations, we propose that the antifungal activity of dodecanol is related to intracellular Ca2+ accumulation, possibly dependent on PMR1 function, with anethole enabling Ca2+ accumulation by restricting dodecanol efflux.

iRGD-targeted hybrid nanoparticles reverses multi-drug resistant to effectively combat liver cancer

The off-target delivery as well as multi-drug resistance (MDR) are generally recognised as two keys difficulties responsible for the poor performance of chemotherapy in clinical treatment of cancer. With the aim to address the problems, we herein constructed iRGD modified and lipid-coated silica (LSC) nanoparticles co-delivering Ca²⁺ channel siRNA and adriamycin (Adr) to reverse the MDR in liver cancer (LSC/R-A). The iRGD decoration was suggested to elevate the tumour accumulation of the drug delivery system (DDS). In addition, the introduction of Ca²⁺ channel siRNA was proved to reverse the MDR within the cells of cancer by regulation the T-type Ca²⁺ channels. Our results showed that decreased expression of T-type Ca²⁺ channels resulted in lowered cytosolic Ca²⁺ level responsible for the cell cycle arrest (at G0/G1 phase) as well as elevated cellular drug retention in HepG2/Adr. B in vitro/in vivo experiments revealed that LSC/R-A exerted highly elevated therapeutic outcome on HepG2/Adr, than administration of single siRNA or Adr.

Synergistic Effect of Benzethonium Chloride Combined with Endoxan against Hepatocellular Carcinoma in Rats through Targeting Apoptosis Signaling Pathway

Combination therapy has been the trendy of care, particularly in cancer remedy, since it is a rational approach to increase response and tolerability and to diminish resistance. Hence, there is a growing interest in combining anticancer drugs to maximizing efficacy with minimum systemic toxicity through the delivery of lower drug doses. Therefore, in the present study, the value of combination between benzethonium chloride (benzo) and endoxan (endo) as anti-tumor drug sensitization of hepatocellular carcinoma HCC treatment were detected both in vitro and in vivo. Crystal violet test was performed to detect the proliferation of HepG2 cells treated with benzo or/and endo. In addition, the HCC rat model was established by diethylnitrosamine (DEN) administration. The antitumor effect was enhanced with the combined treatment of the two drugs, particularly in the group with benzo and endo. The results confirmed that the HCC condition was developed in response to lower expressions of caspase 3 and P53 which, in turn, was due to the overexpression of Bcl-2, and downregulation of cytochrome C. The treatment with benzo combined with endo caused significant activation of caspase-3 mediated apoptotic signals that could be responsible for its anti-HCC potential. Meantime, benzo combined with endo treatments could reduce the hepatocellular carcinogenesis by reducing the expression of MMP-9. Therefore, benzo and endo treatments may be a hopeful therapeutic drug for HCC. Also, more studies are recommended to feat the idea of this research for medical use.

TRP Channels in Digestive Tract Cancers

Cancers of the digestive tract are among the most prevalent types of cancer. These types of cancers are often diagnosed at a late stage, which results in a poor prognosis. Currently, many biomedical studies focus on the role of ion channels, in particular transient receptor potential (TRP) channels, in cancer pathophysiology. TRP channels show mostly non-selective permeability to monovalent and divalent cations. TRP channels are often dysregulated in digestive tract cancers, which can result in alterations of cancer hallmark functions, such as enhanced proliferation, migration, invasion and the inability to induce apoptosis. Therefore, TRP channels could serve as potential diagnostic biomarkers. Moreover, TRP channels are mostly expressed on the cell surface and ion channel targeting drugs do not need to enter the cell, making them attractive candidate drug targets. In this review, we summarize the current knowledge about TRP channels in connection to digestive tract cancers (oral cancer, esophageal cancer, liver cancer, pancreatic cancer, gastric cancer and colorectal cancer) and give an outlook on the potential of TRP channels as cancer biomarkers or therapeutic targets.

Impaired Anti-Tumor T cell Response in Hepatocellular Carcinoma

Different subsets of lymphocytes have the capacity to promote or counteract the progression of solid cancers, including hepatocellular carcinoma (HCC). Therefore, to determine the infiltrative ability and functional status of major immune cell subtypes into tumor may lead to novel insights from the perspective of immunotherapy. After obtaining single cell suspensions from freshly collected specimens of HCC tumor, along with paired peritumor tissues and peripheral blood mononuclear cells (PBMCs) from 14 patients, we flow-cytometrically identified and quantified the relative frequencies of lymphocyte subsets within the tissues of origin. We found that the recruitment in the tumor of cytotoxic cells, namely the terminally differentiated CD4+ and CD8+ T cells (TEFF), is impaired, whereas the effector memory CD4+ T cells (TEM) are more attracted in this site. Concerning the other subsets, the frequency of NK CD56hi and NKT CD56hi cells infiltration in the tumor is increased, whereas that of NKT CD56low is reduced. Although CD4+ and CD8+ T cells settled in the tumor show a higher degree of activation than the circulating counterpart, they occur with a more exhausted phenotype. Overall, these data demonstrate the prevalently immunosuppressive nature of HCC microenvironment, and prompt us to search for strategies to enhance the activity of anti-tumor immune cell subsets.

Ca2+ signaling modulation using cancer cell membrane coated chitosan nanoparticles to combat multidrug resistance of cancer

Off-target drug delivery, together with multidrug resistance (MDR), are two keys obstacles that account for the disappointing outcome in clinical chemotherapy of cancer. To solve these dilemmas, Herein, we constructed cancer cell membrane (CCM) modified silica (CS) nanoparticles (CCM/CS) to co-deliver Ca²⁺ channel siRNA with doxorubicin (DOX) to construct a platform (CCM/CS/R-D) for the efficient therapy of cervical cancer. It was demonstrated that the optimal CCM/CS/R-D was spherical nanoparticles with size at 122.39 ± 4.69 nm and the surface charge of -27.76 ± 3.12 mV. In addition, the CCM/CS/R-D showed acid responsive drug release while high stability under physiological conditions with negligible hemolysis. The CCM/CS/R-D showed CCM mediated cellular uptake and efficient endosomal escape as well as siRNA transfection potential (comparable to that of PEI 25 K) on MDR cervical cancer cells (HeLa/DOX). Most importantly, the MDR of cancer cells was conquered through modulation of T-type Ca²⁺ (Cav) channels. It was observed that the Cav channel siRNA could negatively regulate the level of cytosolic Ca²⁺ concentration which triggered G0/G1 phase cell cycle arrest and elevated intracellular drug retention in HeLa/DOX cells without significantly affect the expression of P-glycolprotein (P-gp). The in vitro and in vivo experiments revealed that CCM/CS/R-D exerted greatly enhanced tumor targetability and therapeutic effect on HeLa/DOX, which was superior than CS/R-D or mono delivery system (CCM/CS/R or CCM/CS/D).

Heparin coated meta-organic framework co-delivering doxorubicin and quercetin for effective chemotherapy of lung carcinoma

Objective

To develop and evaluate a drug delivery system (DDS) capable of targeting cancer cells while at the same time delivering two chemotherapeutic agents to overcome multidrug resistance (MDR).

Methods

This study developed a DDS composed of heparin (HA)-coated meta-organic framework (MOF) nanoparticles (HM) designed to deliver doxorubicin (Dox) and quercetin (Que). A range of in vitro and in vivo studies were conducted to determine the characteristics of the HM/Dox/Que nanoparticles, their ability to produce cytotoxic effects in Dox-resistant A549/Dox cells and target and treat solid tumours in a mouse xenograft model of human lung carcinoma.

Results

This study demonstrated that the HM/Dox/Que nanoparticles reduced cell viability, increased apoptosis, arrested cells in the G0/G1 phase of the cell cycle and reversed MDR in A549/Dox cells in vitro when compared with mono-drug delivery. In a mouse xenograft model of human lung carcinoma, the HM/Dox/Que nanoparticles targeted the tumours and reduced tumour growth as determined by tumour volume.

Conclusion

The use of HM/Dox/Que nanoparticles might be a viable alternative to traditional chemotherapy of lung carcinoma.

Differential engagement of ORAI1 and TRPC1 in the induction of vimentin expression by different stimuli

The Ca²⁺ signal is essential in both hypoxia- and epidermal growth factor (EGF)-mediated epithelial to mesenchymal transition (EMT) in MDA-MB-468 breast cancer cells. This finding suggests that Ca²⁺-permeable ion channels participate in the induction of expression of some mesenchymal markers such as vimentin. However, the ion channels involved in vimentin expression induction have not been fully characterized. This work sought to define how differential modulation of the calcium signal effects the induction of vimentin and the Ca²⁺ influx pathways involved. We identified that the intracellular Ca²⁺ chelator EGTA-AM, cytochalasin D (a modulator of cytoskeletal dynamics and cell morphology), and the sarco/endoplasmic reticulum ATPase inhibitor thapsigargin are all inducers of vimentin in MDA-MB-468 breast cancer cells. EGTA-AM- and thapsigargin-mediated induction of vimentin expression in MDA-MB-468 cells involves store-operated Ca²⁺ entry, as evidenced by sensitivity to silencing of the molecular components of this pathway, STIM1 and ORAI1. In stark contrast, cytochalasin D-mediated vimentin induction was insensitive to silencing of ORAI1, despite sensitivity to silencing of its canonical activator the endoplasmic reticulum Ca²⁺ sensor STIM1. Cytochalasin D-mediated vimentin induction was, however, sensitive to silencing of another reported STIM1 target, TRPC1. Subsequent studies identified that EGTA-AM-induced vimentin expression also partially involved a TRPC1-dependent pathway. These studies define a complex interplay between vimentin expression in this model and the specific Ca²⁺-permeable ion channels involved. The complexity in the engagement of different Ca²⁺ influx pathways that regulate vimentin induction are opportunities but also potential challenges in targeting Ca²⁺ signaling to block EMT in cancer cells. Our findings further highlight the need to identify potential indispensable ion channels that can regulate induction of specific mesenchymal markers via different stimuli.

Cancer Cell Membrane-Decorated Zeolitic-Imidazolate Frameworks Codelivering Cisplatin and Oleanolic Acid Induce Apoptosis and Reversed Multidrug Resistance on Bladder Carcinoma Cells

Combination therapy is emerging as a preferable approach in cancer therapy with minimized side effects and elevated performance. Nevertheless, the poor targeting and drug loading of currently available drug delivery systems (DDSs) are the main difficulties to realize preferable combination therapy of cancer. As a result, a cancer cell membrane-decorated zeolitic-imidazolate framework hybrid nanoparticle (HP) was successfully constructed in our study to codeliver cisplatin (DDP) and oleanolic acid (OLA). Our results showed positive results of the platform (HP/DDP/OLA) for the treatment of bladder cancer (SW780). In detail, HP/DDP/OLA could enhance apoptosis while reverse multidrug resistance in SW780 cells than free drugs alone or monodelivery systems, which might be a suitable DDS for codelivery of different drugs with great promise.

Roles for Ca2+ and K+ channels in cancer cells exposed to the hypoxic tumour microenvironment

For twenty years, ion channels have been studied in cancer progression. Several information have been collected about their involvement in cancer cellular processes like cell proliferation, motility and their participation in tumour progression using in-vivo models. Tumour microenvironment is currently the focus of many researches and the highlighting of the relationship between cancer cells and surrounding elements, is expanding. One of the major physic-chemical parameter involved in tumour progression is the hypoxia conditions observed in solid cancer. Due to their position on the cell membrane, ion channels are good candidates to transduce or to be modulated by environmental modifications. Until now, few reports have been interested in the modification of ion channel activities or expression in this context, compared to other pathological situations such as ischemia reperfusion. The aim of our review is to summarize the current knowledge about the calcium and potassium channels properties in the context of hypoxia in tumours. This review could pave the way to orientate new studies around this exciting field to obtain new potential therapeutic approaches.

Calcium Signaling and the Regulation of Chemosensitivity in Cancer Cells: Role of the Transient Receptor Potential Channels

Cancer cells acquire the ability to modify the calcium signaling network by altering the expression and functions of cation channels, pumps or transporters. Calcium signaling pathways are involved in proliferation, angiogenesis, invasion, immune evasion, disruption of cell death pathways, ECM remodelling, epithelial-mesenchymal transition (EMT) and drug resistance. Among cation channels, a pivotal role is played by the Transient Receptor Potential non-selective cation-permeable receptors localized in plasma membrane, endoplasmic reticulum, mitochondria and lysosomes. Several findings indicate that the dysregulation in calcium signaling induced by TRP channels is responsible for cancer growth, metastasis and chemoresistance. Drug resistance represents a major limitation in the application of current therapeutic regimens and several efforts are spent to overcome it. Here we describe the ability of Transient Receptor Potential Channels to modify, by altering the intracellular calcium influx, the cancer cell sensitivity to chemotherapeutic drugs.