Photostimulated Anticancer Activity of Mitochondria Localized Rhenium(I) Tricarbonyl Complexes Bearing 1H-imidazo[4,5-f][1,10]phenanthroline Ligands Against MDA-MB-231 Cancer Cells.

We have introduced Re(I) tricarbonyl complexes (ReL1 - ReL6) [Re(CO)3(N^N)Cl] where N^N = extensive π conjugated imidazo-[4,5-f]1,10-phenanthroline derivatives that helps in strong DNA intercalation, enhanced photophysical behavior, increase the 3π-π* character of T1 state for PDT and high value of lipophilicity for cell membrane penetration. These complexes exhibited prominent intraligand/ligand-centered (π - π*/ 1LC) absorption bands at λ 260 - 350 nm and relatively weak metal-to-ligand charge-transfer (1MLCT) bands within the λ 350 - 550 nm range. Among the six synthesized complexes, [(CO)3ReICl(K2-N,N-2-(4-(1-benzyl-1H-tetrazol-5-yl)phenyl)-1H-imidazo[4,5-f][1,10]phenanthroline] (ReL6) exhibited outstanding potency (IC50 ~ 6 µM, PI > 9) under yellow light irradiation compared to dark conditions. Importantly, extremely lipophilic complex ReL6 showed effective penetration through the cell membrane and localized primarily in mitochondria (Pearson's correlation coefficient, PCC = 0.918) of MDA-MB-231 cells. Complex ReL6 exhibited more than 9 times higher photo-toxicity in normoxic and hypoxic environment of tumor by inducing 1O2 generation (type II PDT), radical generation triggered by NADH oxidation (type I PDT). This complex is a promising candidate for TNBC treatment in hypoxic tumors, with efficacy comparable to photofrin and have demonstrated CO release ability under UV light irradiation.

Mitochondria-Targeting Click-Derived Pyridinyltriazolylmethylquinoxaline-Based Y-Shaped Binuclear Luminescent Ruthenium(II) and Iridium(III) Complexes as Cancer Theranostic Agents.

Due to several negative issues, market available drugs have been gradually losing their importance in the treatment of cancer. With a view to discover suitable drugs capable of diagnosing as well as inhibiting the growth of cancer cells, we have aspired to develop a group of theranostic metal complexes which will be (i) target specific, (ii) cytoselective, thus rendering the normal cell unaffected, (iii) water-soluble, (iv) cancer cell permeable, and (v) luminescent, being beneficial for healing the cancer eternally. Therefore, to reach our goal, we have prepared novel Ru(II)- and Ir(III)-based bimetallic and hetero bimetallic scaffolds using click-derived pyridinyltriazolylmethylquinoxaline ligands followed by metal coordination. Most of the compounds have displayed significant cytoselectivity against colorectal adenocarcinoma (Caco-2) and epithiloid cervical carcinoma (HeLa) cells with respect to normal human embryonic kidney cells (HEK-293) compared to cisplatin [cis-diamminedichloroplatinum(II)] along with excellent binding efficacy with DNA as well as serum albumin. Complex [(η6-p-cymene)(η5-Cp*)RuIIIrIIICl2(K2-N,N-L)](PF6)2 [RuIrL] exhibited the best cytoselectivity against all the human cancer cells and was identified as the most significant cancer theranostic agent in terms of potency, selectivity, and fluorescence quantum yield. Investigation of the localization of complex [Ir2L] and [RuIrL] in the more aggressive colorectal adenocarcinoma cell HT-29 indicates that mitochondria are the key cellular target for destroying cancer cells. Mitochondrial dysfunction and G2/M phase cell cycle arrest in HT-29 cell were found to be involved in the apoptotic cell death pathway induced by the test complexes [Ir2L] and [RuIrL]. These results validate the concept that these types of complexes will be reasonably able to exert great potential for tumor diagnosis as well as therapy in the near future.

A biomimetic approach to conjugate vitamin B6 cofactor with the lysozyme cocooned fluorescent AuNCs and its application in turn-on sensing of zinc(II) in environmental and biological samples.

This communication focusses on the synthesis of red fluorescent lysozyme cocooned gold nanoclusters (Lyso-AuNCs) that have been successfully applied for the selective and specific recognition of the vitamin B6 cofactor pyridoxal-5'-phosphate (PLP). The red fluorescence of Lyso-AuNCs showed remarkable color change to yellow upon conjugation with PLP due to the formation of a Schiff base between the free -NH2 present in the lysozyme and the -CHO group of PLP. The developed PLP conjugated Lyso-AuNCs (PLP_Lyso-AuNCs) was applied for the selective turn-on recognition of Zn2+ ions in aqueous medium. The yellow fluorescence of PLP_Lyso-AuNCs exhibited significant enhancement at 475 nm in the presence of Zn2+ producing bluish-green fluorescence attributed to the complexation-induced aggregation of nanoclusters. The nanoprobe exhibits nanomolar limit of detection for Zn2+ ions (39.2 nM) and the practicality of the nanoprobe was validated in various environmental water samples and biological plasma, urine, and beetroot extract, with fairly good recovery percent. Also, the system was successfully implemented for the intracellular detection and monitoring of Zn2+ in live HeLa cells. Graphical abstract Applications of red emitting lysozyme cocooned gold nanoclusters (Lyso-AuNCs) for the selective recognition of the vitamin B6 cofactor pyridoxal-5'-phosphate (PLP) and the conjugated nano-assembly PLP_Lyso-AuNCs for turn-on detection of Zn2+ ions in various environmental and biological samples.

Synthesis of novel anticancer ruthenium-arene pyridinylmethylene scaffolds via three-component reaction.

A novel three components approach for the synthesis of bioactive Ru-arene pyridinylmethylene complexes has been developed using pyridine carboxaldehyde, amino pyridine and dichloro (p-cymene) ruthenium(II) dimer as starting materials. These scaffolds were screened for their anticancer activity against breast cancer (MCF7) and human Epitheloid Cervix Carcinoma (HeLa) cell line. It was established that compounds [(η(6)-pcymene)RuCl(κ(2)-N,N-(3,5-dinitro-pyridin-2-yl)-pyridin-2-ylmethylene-amine)]PF6 (4o), [(η(6)-pcymene)RuCl(κ(2)-N,N-N-(3,5-dibromo-pyridin-2-yl)-pyridin-2-ylmethylene-amine)]PF6 (4c), [(η(6)-pcymene)RuCl(κ(2)-N,N-(3,5-dibromo-6-methylpyridin-2-yl)-pyridin-2-ylmethylene-amine)]PF6 (4j) and [(η(6)-pcymene)RuCl(κ(2)-N,N-3(3-bromo-5-methyl-pyridin-2-yl)-pyridin-2-ylmethylene-amine)]PF6 (4b) were significantly active against both the cell lines.

An efficient green synthesis of 2-arylbenzothiazole analogues as potent antibacterial and anticancer agents.

We have demonstrated a novel and green approach for the synthesis of 2-substituted benzothiazole analogues. A number of 2-aryl and heteroaryl benzothiazole scaffolds were synthesized using Amberlite IR-120 resin under microwave irradiation. The catalytic role and reusability of the resin was well established here. 2-Substituted benzothiazole analogues (3a-l) were also tested against several bacterial strains (Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Salmonella) and cancer cell lines (MCF-7 and HeLa). The stability of compound 2-phenyl benzothiazole (3a) and 2-pyridin-2-yl-benzothiazole (3k) in GSH (0.01mM dissolved in DMSO) was measured by UV-Vis spectroscopy. Compound 3k also shows remarkable fluorescence in MeOH.

Synthesis and cytotoxicity study of novel 3-(triazolyl)coumarins based fluorescent scaffolds.

Recently a choice of fluorescent bioimaging probes have been developed as medical diagnostic tools. Herein, we have introduced a series of coumarin-based target specific probes for cancer theranostic application which play a dual role in the field of both diagnosis and therapy. A fluorogenic version of 1,3-dipolar cycloaddition between azides and alkynes (DBCO) has been introduced to develop the triazolylcoumarin based fluorescent scaffolds. These scaffolds were screened for their anticancer activity against breast cancer (MCF7) and human epitheloid cervix carcinoma (HeLa) cell line. It was established that triazolylcoumarins (5c and 5d) are having electronegative substitution in the benzene ring displayed most effective anticancer profile in both the cell lines. Compounds 5a and 5d exhibited maximum quantum yield and strong cellular uptake in the MCF-7 cell line.

Development of surface immobilized 3-azidocoumarin-based fluorogenic probe via strain promoted click chemistry.

A new class of imaging probe, a fluorogenic version of 1, 3-dipolar cycloaddition of azides and alkynes has been developed. 3-azidocoumarin scaffolds were selectively immobilized on the DBCO modified bead surface via SPAAC and provide direct and strong fluorescence in fluorescence microscopy. This developed click-on beads could be applied to label various biomolecules, such as nucleic acids, proteins and other molecules. To this end, 5'(7-hydroxy 3-azido coumarin) labelled DNA primer also displayed strong fluorescence upon successful immobilization on the bead surface.

An efficient synthesis and in vitro antibacterial evaluation of ruthenium-quinolinol complexes.

A series of ruthenium-quinolinol complexes were synthesized using a simple and effective pathway and their in vitro antibacterial activity against various resistant gram-positive and gram-negative bacteria were evaluated. It was established that compound [(η6-pcymene)RuCl(κ2-O,N-5,7-dibromo-HyQ)]·Cl (3b) & [(η6-pcymene)RuCl(κ2-O,N-5,7-dibromo-HyQ)]·Cl (3e) were significantly active against Staphylococcus aureus, Escherichia coli, Bacillus subtilis &Salmonella sp. The structures of the new compounds were elucidated by the analysis of spectroscopic data. The stability of complex [(η6-pcymene)RuCl(κ2-O,N-5,7-dibromo-HyQ)]·Cl (3b) was measured by UV spectroscopy & time dependent NMR spectroscopy. Compound 3b also shows remarkable fluorescence.

Discovery of simplified N²-substituted pyrazolo[3,4-d]pyrimidine derivatives as novel adenosine receptor antagonists: efficient synthetic approaches, biological evaluations and molecular docking studies.

In the present study, a molecular simplification approach was employed to design novel bicyclic pyrazolo[3,4-d]pyrimidine (PP) derivatives from tricyclic pyrazolo[4,3-e]-1,2,4-triazolo-[1,5-c]pyrimidines (PTP) as promising human A3 adenosine receptor (hA3AR) antagonists. All the target compounds were synthesized using novel and efficient synthetic schemes and the structure-activity relationship studies of these PPs were explored through the synthesis of a series of PTP analogues with various substituents. Substituents with different lipophilicity and steric hindrance (e.g., alkyl and aryl-alkyl) functions were introduced at N(2) position of the pyrazole ring, while acyl groups with different electronic properties were introduced at C(6) position of the bicyclic nucleus to probe both electronic and positional effects. Most of the synthesized derivatives of the PP series presented good affinity at the hA3AR, as indicated by the low micromolar range of Ki values and among them, compound 63 with N(2) neopentyl substituents showed most potent hA3AR affinity with Ki value of 0.9 µM and high selectivity (hA1AR/hA3AR=>111 & hA2AAR/hA3AR=>111) towards other adenosine receptor subtypes. Interestingly, small isopropyl groups at N(2) position displayed high affinity at another receptor subtype (hA2AAR, e.g., compound 55, with Ki hA2AAR=0.8 µM), while they were less favorable at the hA3AR. Molecular docking analysis was also performed to predict the possible binding mode of target compounds inside the hA3AR and hA2AAR. Overall, PP derivatives represent promising starting points for new AR antagonists.

Glutathione Depletion and Stalwart Anticancer Activity of Metallotherapeutics Inducing Programmed Cell Death: Opening a New Window for Cancer Therapy.

The cellular defense system against exogenous substances makes therapeutics inefficient as intracellular glutathione (GSH) exhibits an astounding antioxidant activity in scavenging reactive oxygen species (ROS) or reactive nitrogen species (RNS) or other free radicals produced by the therapeutics. In the cancer cell microenvironment, the intracellular GSH level becomes exceptionally high to fight against oxidative stress created by the production of ROS/RNS or any free radicals, which are the byproducts of intracellular redox reactions or cellular respiration processes. Thus, in order to maintain redox homeostasis for survival of cancer cells and their rapid proliferation, the GSH level starts to escalate. In this circumstance, the administration of anticancer therapeutics is in vain, as the elevated GSH level reduces their potential by reduction or by scavenging the ROS/RNS they produce. Therefore, in order to augment the therapeutic potential of anticancer agents against elevated GSH condition, the GSH level must be depleted by hook or by crook. Hence, this Review aims to compile precisely the role of GSH in cancer cells, the importance of its depletion for cancer therapy and examples of anticancer activity of a few selected metal complexes which are able to trigger cancer cell death by depleting the GSH level.

Exploring the phototoxicity of GSH-resistant 2-(5,6-dichloro-1H-benzo[d]imidazol-2-yl)quinoline-based Ir(III)-PTA complexes in MDA-MB-231 cancer cells.

Metal complexes play a crucial role in photo-activated chemotherapy (PACT), which has recently been used to treat specific disorders. Triple-negative breast cancer has an enormously high rate of relapse due to the existence and survival of cancer stem cells (CSCs) characterized by increased amounts of glutathione (GSH). Hence, designing a phototoxic molecule is an enticing area of research to combat triple-negative breast cancer (TNBC) via GSH depletion and DNA photocleavage. Herein, we focus on the application of PTA and non-PTA Ir(III) complexes for phototoxicity in the absence and presence of GSH against MDA-MB-231 TNBC cells. Between these two complexes, [Cp*IrIII(DD)PTA]·2Cl (DDIRP) exhibited better phototoxicity (IC50 ∼ 2.80 ± 0.52 µM) compared to the non-PTA complex [Cp*IrIII(DD)Cl]·Cl (DDIR) against TNBC cells because of the high GSH resistance power of the complex DDIRP. The significant potency of the complex DDIRP under photo irradiation in both normoxia and hypoxia conditions can be attributed to selective transportation, high cellular permeability and uptake towards the nucleus, GSH depletion by GSH-GSSG conversion, the ability of strong DNA binding including intercalation, and oxidative stress. The strong affinity to serum albumin, which serves as a carrier protein, aids in the transport of the complex to its target site while preventing glutathione (GSH) deactivation. Consequently, the complex DDIRP was developed as a suitable phototoxic complex in selective cancer therapy, ruling over the usual chemotherapeutic drug cisplatin and the PDT drug Photofrin. The ability of ROS generation under hypoxic conditions delivers this complex as a hypoxia-efficient selective metallodrug for the treatment of TNBC.

Recent trends in the design and delivery strategies of ruthenium complexes for breast cancer therapy.

As the most frequent and deadly type of cancer in women, breast cancer has a high propensity to spread to the brain, bones, lymph nodes, and lungs. The discovery of cisplatin marked the beginning of the development of anticancer metal-based medications, although the drug's severe side effects have limited its usage in clinical settings. The remarkable antimetastatic and anticancer activity of different ruthenium complexes such as NAMI-A, KP1019, KP1339, etc. reported in the 1980s has bolstered the discovery of ruthenium complexes with various types of ligands for anticancer applications. The review meticulously elucidates the cytotoxic and antimetastatic potential of reported ruthenium complexes against breast cancer cells. Notably, arene-based and cyclometalated ruthenium complexes emerge as standout candidates, showcasing remarkable potency with notably low IC50 values. These findings underscore the promising therapeutic avenues offered by ruthenium-based compounds, particularly in addressing the challenges posed by conventional treatments in refractory or aggressive breast cancer subtypes. Moreover, the review comprehensively integrates a spectrum of ruthenium complexes, spanning traditional metal complexes to nano-based formulations and light-activated variants, underscoring the versatility and adaptability of ruthenium chemistry in breast cancer therapy.

Re(I)[2-aryl-1H-imidazo[4,5-f][1,10]phenanthroline] tricarbonyl chloride complexes for selective cancer therapy via a potential DNA damage mechanism.

Recently, achieving selective cancer therapy with trifling side effects has been a great challenge in the eradication of cancer. Thus, to amplify the cytoselective approach of complexes, herein, we developed a series of Re(I)[2-aryl-1H-imidazo[4,5-f][1,10]phenanthroline] tricarbonyl chloride complexes and screened their potency against HeLa and MCF-7 cell lines together with the evaluation of their toxicity towards a normal kidney cell line (HEK-293). On meticulous investigation, complex [ReI(CO)3Cl(K2-N,N-(2c))] (3c) was found to be the most potent anticancer entity among other complexes. Complex 3c also showed competency to induce apoptosis in MCF-7 cells through G2/M phase cell-cycle arrest in association with the generation of ample reactive oxygen species (ROS), eventually leading to DNA intercalation and internucleosomal cleavage. The order of the cytotoxicity of these complexes depended on their lipophilic character and the electron-withdrawing halogen substitution at the para-position of the phenyl ring in the imidazophenanthroline ligand.

2-Aryl-1H-imidazo[4,5-f][1,10]phenanthroline-Based Binuclear Ru(II)/Ir(III)/Re(I) Complexes as Mitochondria Targeting Cancer Stem Cell Therapeutic Agents.

A series of novel Ru(II)/Ir(III)/Re(I)-based organometallic complexes [Ru2L1, Ru2L2, Ir2L1, Ir2L2, Re2L1, and Re2L2] have been synthesized to assess their potency and selectivity against multiple cancer cells A549, HCT-116, and HCT-116 colon CSCs. The cytotoxic screening of the synthesized complexes has revealed that complex Ru2L1 and Ir2L2 are two proficient complexes among all, but Ru2L1 is the most potent complex. A significant binding constant value was observed for DNA and BSA in all complexes. Significant lipophilic properties allow them to penetrate cancer cell membranes, and substantial quantum yield (ϕf) values support bioimaging potential. Again, these complexes are particular for mitochondrial localization and produce a profuse amount of ROS to damage the mitochondrial DNA and then G1 phase cell-cycle arrest. Protein expression analysis unveiled that pro-apoptotic Bax protein overexpressed in Ru2L1-treated cells, whereas antiapoptotic Bcl-2 protein was expressed twofold in Ir2L2-treated cells, which correlated with autophagy reticence.

Organoruthenium antagonists of human A3 adenosine receptors.

Human A3 adenosine receptor (A3AR) is a membrane-bound G protein-coupled receptor implicated in a number of severe pathological conditions, including cancer, in which it acts as a potential therapeutic target. To derive structure-activity relationships on pyrazolo-triazolo-pyrimidine (PTP)-based A3AR antagonists, we developed a new class of organometallic inhibitors through replacement of the triazolo moiety with an organoruthenium fragment. The objective was to introduce by design structural diversity into the PTP scaffold in order to tune their binding efficacy toward the target receptor. These novel organoruthenium antagonists displayed good aquatic stability and moderate binding affinity toward the hA3 receptor in the low micromolar range. The assembly of these complexes through a template-driven approach with selective ligand replacement at the metal center to control their steric and receptor-binding properties is discussed.

Synthesis, characterization, photophysical and electrochemical properties, and biomolecular interaction of 2,2'-biquinoline based phototoxic Ru(II)/Ir(II) complexes.

The phototoxic nature of drugs has been seen to convey immense importance in photo activated chemotherapy (PACT) for the selective treatment of disease. Rationally, in order to eradicate the vehemence of cancer in a living body, the design of phototoxic molecules has been of growing interest in research to establish a selective strategy for cancer therapy. Therefore, the present work portrays the synthesis of a phototoxic anticancer agent by incorporating ruthenium(II) and iridium(III) metals into a biologically active 2,2'-biquinoline moiety, BQ. The complexes, RuBQ and IrBQ, have been revealed as effective anticancer agents with remarkable toxicity in the presence of light compared to the dark towards HeLa and MCF-7 cancer cell lines due to the production of a profuse amount of singlet oxygen (1O2) upon irradiation by visible light (400-700 nm). Complex IrBQ exhibited the best toxicity (IC50 = 8.75 µM in MCF-7 and 7.23 µM in HeLa) in comparison to the RuBQ complex under visible light. RuBQ and IrBQ displayed considerable quantum yields (Φf) along with a good lipophilic property, indicating the cellular imaging capability of both complexes upon significant accumulation in cancer cells. Also, the complexes have shown significant binding propensity with biomolecules, viz. deoxyribonucleic acid (DNA) as well as serum albumin (BSA, HSA).

GSH resistant, luminescent 2-(pyren-1-yl)-1H-imidazo[4,5-f][1,10]phenanthroline-based Ru(II)/Ir(III)/Re(I) complexes for phototoxicity in triple-negative breast cancer cells.

Selective chemotherapeutic strategies necessitate the emergence of a photosensitive scaffold to abate the nuisance of cancer. In the current context, photo-activated chemotherapy (PACT) has, therefore, appeared to be very effective to vanquish the vehemence of triple-negative breast cancer (TNBC). Metal complexes have been identified to act well against cancer cell microenvironment (high GSH content, low pH, and hypoxia), and thus they have been employed in the treatment of various types of cancer. As TNBC is very challenging to treat owing to its poor prognosis, lack of a specific target, high chance of relapse, and strong metastatic ability, herein we have aspired to design GSH-resistant phototoxic Ru(II)/Ir(III)/Re(I) based pyrene imidazophenathroline complexes to selectively avert the triple-negative breast cancer. The application of complexes, [RuL], [IrL], and [ReL] in the absence and in the presence of GSH against MDA-MB-231TNBC cells, has revealed that they are very active upon irradiation of visible light compared to dark due to the creation of copious singlet oxygen (1O2) as reactive oxygen species (ROS). Among three synthesized complexes, [IrL] has shown outstanding potency (IC50 = 3.70 in the absence of GSH and IC50 = 3.90 in the presence of GSH). Also, the complex, [IrL] is capable of interacting with DNA with the highest binding constant (Kb = 0.023 × 106 M-1) along with higher protein binding affinity (KBSA = 0.0321 × 106 M-1). Here, it has been unveiled that all the complexes have been entitled to involve DNA covalent interaction through the available sites of both adenine and guanine bases.

CuAAC "Click"-Derived Luminescent 2-(2-(4-(4-(Pyridin-2-yl)-1H-1,2,3-triazol-1-yl)butoxy)phenyl)benzo[d]thiazole-Based Ru(II)/Ir(III)/Re(I) Complexes as Anticancer Agents.

To enhance the cytoselective behavior of the complexes, we intended to develop a CuAAC "click"-derived synthetic protocol for the preparation of 2-(2-(4-(4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl)butoxy)phenyl)benzo[d]thiazole-based Ru(II)/Ir(III)/Re(I) complexes, and their cytotoxicity against three different cancer cell lines (MCF-7, HeLa, and U87MG) in consort with one normal cell line (HEK-293) was evaluated. In our detailed investigations, the significant cytotoxic nature of the Ru(II) complex 7a compared to Ir(III) and Re(I) complexes (7b and 7c, respectively) was observed. Complex 7a was capable of MCF-7 cell apoptosis via the inhibition of both S- and G2/M-phase cell cycle arrest in association with a substantial quantity of ROS production and DNA intercalation.

Different routes for the construction of biologically active diversely functionalized bicyclo[3.3.1]nonanes: an exploration of new perspectives for anticancer chemotherapeutics.

Cancer is the second most high-morbidity disease throughout the world. From ancient days, natural products have been known to possess several biological activities, and research on natural products is one of the most enticing areas where scientists are engrossed in the extraction of valuable compounds from various plants to isolate many life-saving medicines, along with their other applications. It has been noticed that the bicyclo[3.3.1]nonane moiety is predominant in most biologically active natural products owing to its exceptional characteristics compared to others. Many derivatives of bicyclo[3.3.1]nonane are attractive to researchers for use in asymmetric catalysis or as potent anticancer entities along with their successful applications as ion receptors, metallocycles, and molecular tweezers. Therefore, this review article discusses several miscellaneous synthetic routes for the construction of bicyclo[3.3.1]nonanes and their heteroanalogues in association with the delineation of their anticancer activities with few selective compounds.

Luminescent 11-{Naphthalen-1-yl}dipyrido[3,2-a:2',3'-c]phenazine-Based Ru(II)/Ir(III)/Re(I) Complexes for HCT-116 Colorectal Cancer Stem Cell Therapy.

Due to a number of unpleasant considerations, marketed drugs have steadily lost their importance in the treatment of cancer. In order to find a viable cancer cell diagnostic agent, we therefore focused on metal complexes that displayed target adequacy, permeability to cancer cells, high standard water solubility, cytoselectivity, and luminescent behavior. In this aspect, luminescent 11-{naphthalen-1-yl} dipyrido [3,2-a:2',3'-c] phenazine based Ru(II)/Ir(III)/Re(I) complexes have been prepared for HCT-116 colorectal cancer stem cell therapy. Our study successfully established the possible cytotoxicity of IrL complex at different doses on HCT-116 colorectal cancer stem cells (CRCSCs). Additionally, an immunochemistry analysis of the complex IrL showed that the molecule was subcellularly localized in the nucleus and other regions of the cytoplasm, where it caused nuclear DNA damage and mitochondrial dysfunction. The level of BAX and Bcl-2 was further quantified by qRT-PCR. The expression of proapoptotic BAX showed increased expression in the complex IrL-treated cell compared to the control, indicating the potential of complex IrL for apoptotic induction. Upon further validation, complex IrL was developed as an inhibitor of autophagy for the eradication of cancer stem cells.