Non-genetic heterogeneity and immune subtyping in breast cancer: Implications for immunotherapy and targeted therapeutics.

Breast cancer (BC) is a complex and multifactorial disease, driven by genetic alterations that promote tumor growth and progression. However, recent research has highlighted the importance of non-genetic factors in shaping cancer evolution and influencing therapeutic outcomes. Non-genetic heterogeneity refers to diverse subpopulations of cancer cells within breast tumors, exhibiting distinct phenotypic and functional properties. These subpopulations can arise through various mechanisms, including clonal evolution, genetic changes, epigenetic changes, and reversible phenotypic transitions. Although genetic and epigenetic changes are important points of the pathology of breast cancer yet, the immune system also plays a crucial role in its progression. In clinical management, histologic and molecular classification of BC are used. Immunological subtyping of BC has gained attention in recent years as compared to traditional techniques. Intratumoral heterogeneity revealed by immunological microenvironment (IME) has opened novel opportunities for immunotherapy research. This systematic review is focused on non-genetic variability to identify and interlink immunological subgroups in breast cancer. This review provides a deep understanding of adaptive methods adopted by tumor cells to withstand changes in the tumor microenvironment and selective pressure imposed by medications. These adaptive methods include alterations in drug targets, immune system evasion, activation of survival pathways, and alterations in metabolism. Understanding non-genetic heterogeneity is essential for the development of targeted therapies.

Synthesis of novel carbazole hydrazine-carbothioamide scaffold as potent antioxidant, anticancer and antimicrobial agents.

BACKGROUND: Carbazole-based molecules containing thiosemicarbazide functional groups are recognized for their diverse biological activities, particularly in enhancing therapeutic anticancer effects through inhibiting crucial pathways. These derivatives also exhibit noteworthy antioxidant properties. OBJECTIVES: This study aims to synthesize, characterize, and evaluate the antioxidant and anticancer activities of 18 novel carbazole derivatives. METHODS: The radical scavenging capabilities of the compounds were assessed using the 2,2-diphenyl-1-picrylhydrazyl assay. Antiproliferative activities were evaluated on MCF-7 cancer cell lines through viability assays. Additionally, the modulation of the PI3K/Akt/mTOR pathway, apoptosis/necrosis induction, and cell cycle analysis were conducted for the most promising anticancer agents. RESULTS: nine compounds showed potent antioxidant activities with IC50 values lower than the positive control acarbose, with compounds 4 h and 4y exhibiting the highest potency (IC50 values of 0.73 and 0.38 µM, respectively). Furthermore, compounds 4o and 4r displayed significant anticancer effects, with IC50 values of 2.02 and 4.99 µM, respectively. Compound 4o, in particular, exhibited promising activity by targeting the PI3K/Akt/mTOR signaling pathway, inhibiting tumor survival, inducing apoptosis, and causing cell cycle arrest in MCF-7 cell lines. Furthermore, compound 4o was showed significant antimicrobial activities against S. aureus and E. coli, and antifungal effect against C. albicans. Its potential to overcome drug resistance through this pathway inhibition highlights its promise as an anticancer agent. Molecular docking simulations supported these findings, revealing favorable binding profiles and interactions within the active sites of the enzymes PI3K, AKT1, and mTOR. Moreover, assessing the druggability of the newly synthesized thiosemicarbazide derivatives demonstrated optimal physicochemical properties, further endorsing their potential as drug candidates.

Metabologenomics and network pharmacology to understand the molecular mechanism of cancer research.

In this editorial I comment on the article "Network pharmacological and molecular docking study of the effect of Liu-Wei-Bu-Qi capsule on lung cancer" published in the recent issue of the World Journal of Clinical Cases 2023 November 6; 11 (31): 7593-7609. Almost all living forms are able to manufacture particular chemicals-metabolites that enable them to differentiate themselves from one another and to overcome the unique obstacles they encounter in their natural habitats. Numerous methods for chemical warfare, communication, nutrition acquisition, and stress prevention are made possible by these specialized metabolites. Metabolomics is a popular technique for collecting direct measurements of metabolic activity from many biological systems. However, confusing metabolite identification is a typical issue, and biochemical interpretation is frequently constrained by imprecise and erroneous genome-based estimates of enzyme activity. Metabolite annotation and gene integration uses a biochemical reaction network to obtain a metabolite-gene association so called metabologenomics. This network uses an approach that emphasizes metabolite-gene consensus via biochemical processes. Combining metabolomics and genomics data is beneficial. Furthermore, computer networking proposes that using metabolomics data may improve annotations in sequenced species and provide testable hypotheses for specific biochemical processes.

Hsp Inhibitor is Affective Against Adenocarcinomic Human Alveolar Basal Epithelial Cells Through Modulating ERK/MAPK Signaling Pathway.

The extracellular signal-regulated kinase (ERK) - mitogen-activated protein kinase (MAPK) pathway regulates cell proliferation, differentiation, and apoptosis. Heat Shock Protein 90 (HSP90) is required to activate proto-oncogenic protein kinases and promotes tumor growth through anti-apoptotic effects on A549-non-small cell lung cancer (NSCLC). Therefore, deregulation of the ERK-MAPK pathway and abnormal expression of HSP90 are reasonably frequent events in NSCLC. In this study, novel perimidine-pyrazole compounds employed to block ERK-MAPK deregulation through inhibiting HSP dependent cancer cell survival mechanisms. A set of perimidine-pyrazole derivatives effects was monitored on NSCLC cell line. Array experiments performed to understand the effect of the compounds on signaling pathways and results were analyzed by gene enrichment analysis. Further, senescence and apoptosis experiments were performed to support the enrichment results along with in silico methods to determine perimidine-pyrazole/HSP interactions. Treatment of NSCLC cells with perimidine-pyrazole derivatives displayed cancer-inhibitory, pro-senescent and pro-apoptotic effects on NSCLC cells through ERK/MAPK pathway and these compounds are promising templates for designing anticancer drugs.

Triad pyrazole-thiazole-coumarin heterocyclic core effectively inhibit HSP and drive cancer cells to apoptosis.

Intensive studies on hepatocellular carcinoma (HCC), which is spreading rapidly around the world and has a high mortality rate, is due to the lack of adequate preventive or curative treatment methods. Treating patients with HCC has become very challenging because of the heterogeneity in the patient population lead activation of different signaling pathways, and pathway crosstalk for patients. Therefore, understanding these molecular mechanisms and combining drugs with molecular therapies to overcome these drawbacks has become an area of utmost importance. In this study, the biological activities of the designed and characterized triad Pyrazole-Thiazol-Coumarin (PTC) compounds were determined by performing cell viability, qPCR array, apoptosis and cell cycle assays. One of the compounds (PTC10) implicitly suppresses multiple pathways (RAS/MAP kinase and PI3K-AKT) simultaneously. This action is provided by (i) arresting cancer cells at G2 phase, (ii) driving cancer cells to apoptosis and (iii) inhibiting HSP network. Remarkably, HSP is an apoptotic factor and help cancer cell to survive. HSP90 also coordinates with Cdk4/Cdc37, therefore inhibiting HSP both drives cells to arrest and apoptosis. ATP hydrolysis and aggregation assay further displayed specific HSP inhibition. Therefore, PTC provides a unique drug template for HCC treatment.

Pralatrexate for Peripheral T-Cell Lymphoma (PTCL): Chance Only Supports The Prepared Mind.

BACKGROUND: Due to their primary effects on DNA synthesis, antimetabolites are most effective against actively dividing cells and are significantly specific to the cell cycle phase. Pralatrexate (PDX), an antifolate metabolite designed to accumulate in cancer cells, was the first new agent approved by the US Food and Drug Administration for the treatment of resistant/recurrent peripheral T-cell lymphomas. PDX was a drug that is frequently used not only for PTCL, but also for cutaneous T-cell lymphoma (CTCL), extranodal natural killer (NK) / T-cell lymphoma. OBJECTIVE: This article reviews Pralatrexate's history, pharmacokinetics, clinical phase studies including phases I, II and III, types of cancers it is effective on, drug side effects, inhibition mechanism and even its use in the treatment of other cancers with innovative methods, including its antiviral effect against SARS-CoV-2 infection. METHODS: A comprehensive internet-based research was planned, covering all published and unpublished studies on the subject. We conducted this review in accordance with Preferred Reporting Items for systematic reviews and metaanalysis (PRISMA-P), and Cochrane Collaboration reporting items for systematic reviews and meta-analysis. The results of the studies in the articles were recorded to include all phase studies. RESULTS: Pralatrexate was structurally designed to have enhanced cellular transport via RFC (reduced folate carrier type) and be subject to more polyglutamation compared to methotrexate. The enhanced polyglutamylation ability of pralatrexate is associated with increased tumor cell death and ultimately improved anticancer activity. Pralatrexate is considered a promising drug for patients with recurrent and treatment-resistant PTCL with a good survival advantage. At the same time, it is an antifolate agent with a significant advantage over methotrexate as it does not cause myelosuppression. CONCLUSION: While there are manageable side effects such as thrombocytopenia, neutropenia, and mucositis, it is critical to explore new approaches, targeted agents, novel cellular therapies, and immunotherapies to determine optimal pretreatment in the rare but heterogeneous disease PTCL, and future studies and experienced haematologists are needed.

Involvement of Metabolites and Non-coding RNAs in Diseases.

Non-coding RNAs have a role in gene regulation and cellular metabolism control. Metabolism produces metabolites which are small molecules formed during the metabolic process. So far, a direct relationship between metabolites and genes is not fully established; however, pseudogenes and their progenitor genes regulate health and disease states. Other non-coding RNAs also contribute to this regulation at different cellular processes. Accumulation and depletion of metabolites accompany the dynamic equilibrium of health and disease state. In this study, metabolites, their roles in the cell, and the link between metabolites and non-coding RNAs are discussed.

A Novel 6,8,9-Trisubstituted Purine Analogue Drives Breast Cancer Luminal A Subtype MCF-7 to Apoptosis and Senescence through Hsp70 Inhibition.

BACKGROUND: Cancer cells restrain apoptotic and senescence pathways through intracellular heat shock protein 70 (Hsp 70). These cells aid stimulus-independent growth, and their higher metabolism rate requires Hsps. Hsps compensate abnormally increased substrate protein folding rate of cancer cells. OBJECTIVE: Misfolding of substrate proteins especially signaling substrate proteins, may not function properly. Therefore, Hsp70 folds these substrate proteins into their native-fully functional states, and this mode of action helps cancer cell survival. METHODS: Targeting Hsps is promising cancer therapy, and in this study, 6,8,9-trisubstituted purine derivatives were designed and synthesized to inhibit Hsp70 and drive cancer cells to apoptosis. Further, oncogenic stimuli through inhibitors can induce an irreversible senescent state and senescence is a barrier to transformation. RESULTS: Hsp70 helps cancer cells to bypass the cellular senescence program, however, binding of N6-(4- isopropylaniline) analogue (7) depletes Hsp70 function as evidenced by aggregation assay and Hsp70 depletion induces senescence pathway. CONCLUSION: The purine-based inhibitor-compound 7 effectively inhibits MCF-7 cell line. Moreover, the therapeutic potential with regard to the senescence-associated secretory phenotype has complementary action. Dual action of the inhibitor not only drives the cells to apoptosis but also force the cells to be in the senescence state and provides promising results specially for luminal A type breast cancer therapy.

Silver(I) Complexes Based on Oxadiazole-Functionalized α-Aminophosphonate: Synthesis, Structural Study, and Biological Activities.

Two silver(I) complexes, bis{diethyl[(5-phenyl-1,3,4-oxadiazol-2-yl-κN3:κN4-amino) (4-trifluoromethylphenyl)methyl]phosphonate-(tetrafluoroborato-κF)}-di-silver(I) and tetrakis-{diethyl[(5-phenyl-1,3,4-oxadiazol-2-yl-κN3-amino)(4-trifluoromethylphenyl)methyl]phosphonate} silver(I) tetrafluoroborate, were prepared starting from the diethyl[(5-phenyl-1,3,4-oxadiazol-2-yl-amino)(4-trifluoromethylphenyl)methyl]phosphonate (1) ligand and AgBF4 salt in Ag/ligand ratios of 1/1 and 1/4, respectively. The structure, stoichiometry, and geometry of the silver complexes were fully characterized by elemental analyses, infrared, single-crystal X-ray diffraction studies, multinuclear NMR, and mass spectroscopies. The binuclear complex ([Ag2(1)2(BF4)2]; 2) crystallizes in the monoclinic asymmetric space group P21/c and contains two silver atoms adopting a {AgN2F} planar trigonal geometry, which are simultaneously bridged by two oxadiazole rings of two ligands, while the mononuclear complex ([Ag(1)4]BF4; 3) crystallizes in the non-usual cubic space group Fd-3c in which the silver atom binds to four distinct electronically enriched nitrogen atoms of the oxadiazole ring, in a slightly distorted {AgN4} tetrahedral geometry. The α-aminophosphonate and the monomeric silver complex were evaluated in vitro against MCF-7 and PANC-1 cell lines. The silver complex is promising as a drug candidate for breast cancer and the pancreatic duct with half-maximal inhibitory concentration (IC50) values of 8.3 ± 1.0 and 14.4 ± 0.6 µM, respectively. Additionally, the interactions of the ligand and the mononuclear complex with Vascular Endothelial Growth Factor Receptor-2 and DNA were evaluated by molecular docking methods.

Computational Analysis of Drug Resistance Network in Lung Adenocarcinoma.

BACKGROUND: Lung cancer is a significant health problem and accounts for one-third of the deaths worldwide. A great majority of these deaths are caused by Non-Small Cell Lung Cancer (NSCLC). Chemotherapy is the leading treatment method for NSCLC, but resistance to chemotherapeutics is an important limiting factor that reduces the treatment success of patients with NSCLC. OBJECTIVE: In this study, the relationship between differentially expressed genes affecting the survival of the patients, according to the bioinformatics analyses, and the mechanism of drug resistance is investigated for nonsmall cell lung adenocarcinoma patients. METHODS: Five hundred thirteen patient samples were compared with fifty-nine control samples. The employed dataset was downloaded from The Cancer Genome Atlas (TCGA) database. The information on how the drug activity altered against the expressional diversification of the genes was extracted from the NCI-60 database. Four hundred thirty-three drugs with known Mechanism of Action (MoA) were analyzed. Diversifications of the activity of these drugs related to genes were considered based on nine lung cancer cell lines virtually. The analyses were performed using R programming language, GDCRNATools, rcellminer, and Cytoscape. RESULTS: This work analyzed the common signaling pathways and expressional alterations of the proteins in these pathways associated with survival and drug resistance in lung adenocarcinoma. Deduced computational data demonstrated that proteins of EGFR, JNK/MAPK, NF-κB, PI3K /AKT/mTOR, JAK/STAT, and Wnt signaling pathways were associated with the molecular mechanism of resistance to anticancer drugs in NSCLC cells. CONCLUSION: To understand the relationships between resistance to anticancer drugs and EGFR, JNK/MAPK, NF-κB, PI3K /AKT/mTOR, JAK/STAT, and Wnt signaling pathways is an important approach to design effective therapeutics for individuals with NSCLC adenocarcinoma.

MicroRNA Targeting.

MicroRNAs (miRNAs) are small noncoding elements that play essential roles in the posttranscriptional regulation of biochemical processes. miRNAs recognize and target multiple mRNAs; therefore, investigating miRNA dysregulation is an indispensable strategy to understand pathological conditions and to design innovative drugs. Targeting miRNAs in diseases improve outcomes of several therapeutic strategies thus, this present study highlights miRNA targeting methods through experimental assays and bioinformatics tools. The first part of this review focuses on experimental miRNA targeting approaches for elucidating key biochemical pathways. A growing body of evidence about the miRNA world reveals the fact that it is not possible to uncover these molecules' structural and functional characteristics related to the biological processes with a deterministic approach. Instead, a systemic point of view is needed to truly understand the facts behind the natural complexity of interactions and regulations that miRNA regulations present. This task heavily depends both on computational and experimental capabilities. Fortunately, several miRNA bioinformatics tools catering to nonexperts are available as complementary wet-lab approaches. For this purpose, this work provides recent research and information about computational tools for miRNA targeting research.

MicroRNAs and Heat Shock Proteins in Breast Cancer Biology.

Breast cancer has five major immune types; luminal A, luminal B, HER2, Basal-like, and normal-like. Cells produce a family of protein called heat shock proteins (Hsps) in response to exposure to thermal and other proteotoxic stresses play essential roles in cancer metabolism and this large family shows a diverse set of Hsp involvement in different breast cancer immune types. Recently, Hsp members categorized according to their immune type roles. Hsp family consists of several subtypes formed by molecular weight; Hsp70, Hsp90, Hsp100, Hsp40, Hsp60, and small molecule Hsps. Cancer cells employ Hsps as survival factors since most of these proteins prevent apoptosis. Several studies monitored Hsp roles in breast cancer cells and reported Hsp27 involvement in drug resistance, Hsp70 in tumor cell transformation-progression, and interaction with p53. Furthermore, the association of Hsp90 with steroid receptors and signaling proteins in patients with breast cancer directed research to focus on Hsp-based treatments. miRNAs are known to play key roles in all types of cancer that are upregulated or downregulated in cancer which respectively referred to as oncogenes (oncomirs) or tumor suppressors. Expression profiles of miRNAs may be used to classify, diagnose, and predict different cancer types. It is clear that miRNAs play regulatory roles in gene expression and this work reveals miRNA correlation to Hsp depending on specific breast cancer immune types. Deregulation of specific Hsp genes in breast cancer subtypes allows for identification of new targets for drug design and cancer treatment. Here, we performed miRNA network analysis by recruiting Hsp genes detected in breast cancer subtypes and reviewed some of the miRNAs related to aforementioned Hsp genes.

44 Current Challenges in miRNomics.

Mature microRNAs (miRNAs) are short RNA sequences about 18-24 nucleotide long, which provide the recognition key within RISC for the posttranscriptional regulation of target RNAs. Considering the canonical pathway, mature miRNAs are produced via a multistep process. Their transcription (pri-miRNAs) and first processing step via the microprocessor complex (pre-miRNAs) occur in the nucleus. Then they are exported into the cytosol, processed again by Dicer (dsRNA) and finally a single strand (mature miRNA) is incorporated into RISC (miRISC). The sequence of the incorporated miRNA provides the function of RNA target recognition via hybridization. Following binding of the target, the mRNA is either degraded or translation is inhibited, which ultimately leads to less protein production. Conversely, it has been shown that binding within the 5' UTR of the mRNA can lead to an increase in protein product. Regulation of homeostasis is very important for a cell; therefore, all steps in the miRNA-based regulation pathway, from transcription to the incorporation of the mature miRNA into RISC, are under tight control. While much research effort has been exerted in this area, the knowledgebase is not sufficient for accurately modelling miRNA regulation computationally. The computational prediction of miRNAs is, however, necessary because it is not feasible to investigate all possible pairs of a miRNA and its target, let alone miRNAs and their targets. We here point out open challenges important for computational modelling or for our general understanding of miRNA-based regulation and show how their investigation is beneficial. It is our hope that this collection of challenges will lead to their resolution in the near future.

Performance of capecitabine in novel combination therapies in colorectal cancer.

Colorectal cancer is one of the most common cancers throughout the world, and no definitive cure has ever been found. Perhaps a new insight into the effectiveness of chemotherapy drugs could help better treat patients. Targeted therapies have significantly improved the median overall survival of colorectal cancer patients. One of the standard chemotherapy regimens used for colorectal cancer is capecitabine, which is important in monotherapy and combination therapies. Capecitabine, with other chemotherapeutic agents (irinotecan, oxaliplatin, perifosine, 17-allylamino-17-demethoxygeldanamycin, aspirin, celecoxib, statins, quinacrine, inositol hexaphosphate and inositol, cystine/theanine, curcumin, and isorhamnetin), and biological ones (antibodies) plays an important role in the inhibition of some signaling pathways, increasing survival, reducing tumor growth and side effects of capecitabine. However, some drugs, such as proton pump inhibitors, are negatively related to capecitabine; therefore, the purpose of this work is to review and discuss the performance of capecitabine combination therapies in colorectal cancer.

ATPase inhibition by omeprazole reveals role of heat shock proteins on testicular torsion.

Testicular torsion leads ischaemic injury and generates reactive oxygen species. Reactive oxygen species triggers lipid peroxidation, protein degradation and DNA damage. These biochemical processes trigger tissue damage. Heat shock proteins (HSPs) are important in spermatogenesis, and this work elucidates role of HSPs at the testicular torsion-detorsion process. A proton-pump inhibitor, omeprazole, tested to reveal the drug's curative effect since HSP functions through ATP hydrolysis. Thirty-two male Wistar Albino rats were divided into four groups: sham, control, omeprazole and serum physiologic groups. Right testis was torsed, while left ones remained untorsed. Protein peroxidation, DNA damage and lipid hydroperoxide levels as well as HSP expression were measured. Further, the effects were visualised with histopathologic imaging. HSP expression increases at the torsed right testis compared to the contralateral testis. Although HSP70 and HSP90 help antioxidant enzymes to keep their native structure, their anti-apoptotic properties accelerate the tissue damage. Omeprazole a proton-pump inhibitor employed to impair electron transfer chain and to inhibit HSP ATPase function. Omeprazole effectively inhibits HSPs and alleviates lipid peroxidation and DNA damage levels both at molecular and at tissue level, and the drug has profound curative effect on testicular torsion recovery.

Designing Specific HSP70 Substrate Binding Domain Inhibitor for Perturbing Protein Folding Pathways to Inhibit Cancer Mechanism.

BACKGROUND: HSP70 is a survival factor for tumor cells in transformation and in tumor progression as well as in anti-apoptotic response. OBJECTIVE: Several inhibitors targeting HSP70 ATPase function displayed off-target effects, but PES, which targets the HSP70 substrate binding domain, prevents tumor cell survival prominently. However, PES may not bind HSP70 in the absence of nucleotide. This research aimed to design a unique inhibitor molecule that works both in the presence and absence of nucleotides to amplify inhibition. METHODS: A set of chimeric coumarine-pyrazole derivatives were determined by in silico techniques and synthesized to elucidate their inhibitory effects. Cell viability experiments displayed KBR1307 as the most efficient inhibitor. A set of characterization experiments were performed, and the results were compared to that of PES agent. Binding constant, ATP hydrolysis rate, and percent aggregation were determined in the presence and absence of inhibitors. RESULTS: In silico docking experiments showed that only KBR1307 binds the HSP70 substrate binding domain and interacts with cochaperone interface. Binding experiments indicated that KBR1307 binds HSP70 both in the presence and absence of nucleotides, but PES does not. Both inhibitors significantly lower HSP70 ATPase activity and substrate protein disaggregation activity. However, KBR1307 displays a lower IC50 value at the MCF-7 cell line compared to PES. Both inhibitors do not alter HSP70 secondary structure composition and overall stability. CONCLUSION: KBR1307 effectively inhibits HSP70 compared to PES and provides a promising template for novel anticancer drug development.

Assessment of plasma and tissue fibronectin EIIIB splice variant expressions measured serially using RT-PCR in a wound model of rabbits.

BACKGROUND: Fibronectin (FN) is an indispensable part of the extracellular matrix. During regeneration or wound healing, the plasma form of FN is incorporated into the fibrin clots to form a temporary fibrin-FN matrix, and also locally synthesized cellular FN migrates to the clot to regenerate the injured tissue. We aimed to examine wound tissue FN EIIIB and plasma FN EIIIB expression levels in an experimental wound healing model in rabbits. METHODS: Plasma and tissue EIIIB splice variant expressions were measured serially with RT-qPCR in a cutaneous wound model of rabbits. RESULTS: Tissue FN expression increased as beginning on day 3 and continued to increase on days 6 and 9, reaching maximum expression at day 12 before starting to decrease. On the contrary to the tissue levels, plasma FN levels gradually decreased until day 15 when expression returned to the initial values. CONCLUSION: The findings of the current study support that tissue EIIIB expression level increases during wound healing; and plasma EIIIB expression level decreases minimal changed. This is in contrast to reports where plasma FN provisionally helps ECM formation. Therefore, our data show an essential role of EIIIB at the tissue level in accelerating the wound healing process. The RT-qPCR method in our experimental setup can provide more accurate and precise results compared to the antibody-based methods.

Perturbation of HSP Network in MCF-7 Breast Cancer Cell Line Triggers Inducible HSP70 Expression and Leads to Tumor Suppression.

BACKGROUND: Heat shock protein 70 (HSP70) is constitutively expressed in normal cells but aberrantly expressed in several types of tumor cells, helping their survival in extreme conditions. Thus, specific inhibition of HSP70 in tumor cells is a promising strategy in the treatment of cancer. HSP70 has a variety of isoforms in the cellular organelles and form different functions by coordinating and cooperating with cochaperones. Cancer cells overexpress HSPs during cell growth and proliferation and HSP network provides resistance against apoptosis. The present study aimed to evaluate quantitative changes in HSPs- and cancerassociated gene expressions and their interactions in the presence of 2-phenylethyenesulfonamide (PES) in MCF-7 cells. METHODS: Antiproliferative activity of PES was evaluated using the XTT assay. Inducible HSP70 (HSP70i) levels in the PES-treated cells were determined using the ELISA kit. PCR Array was performed to assess the HSPs- and cancer-pathway focused gene expression profiling. Gene network analysis was performed using the X2K, yEd (V.3.18.1) programs, and web-based gene list enrichment analysis tool Enrichr. RESULTS: The results demonstrated that PES exposure increased the amount of both HSP70i gene and protein expression surprisingly. However, the expression of HSP70 isoforms as well as other co-chaperones, and 17 cancer-associated genes decreased remarkably as expected. Additionally, interaction network analysis revealed a different mechanism; PES induction of HSP70i employs a cell cycle negative regulator, RB1, which is a tumor suppressor gene. CONCLUSION: PES treatment inhibited MCF-7 cell proliferation and changed several HSPs- and cancer-related gene expressions along with their interactions through a unique mechanism although it causes an interesting increase at HSP70i gene and protein expressions. RB1 gene expression may play an important role in this effect as revealed by the interaction network analysis.