Cancer Cell DNA Research Articles

Synthesis and Characterization of Ruthenium-Paraphenylene-Cyclopentadienyl Full-Sandwich Complexes: Cytotoxic Activity against A549 Lung Cancer Cell Line and DNA Binding Properties.

Novel full-sandwich (η5-Cp)-Ru-paraphenylene complexes with the general formula [(η5-Cp)nRu(η6-L)](PF6)n where n = 1-3 and L = biphenyl, p-terphenyl and p-quaterphenyl, were synthesized and characterized by means of spectroscopic and analytical techniques. The structures of the complexes [(η5-Cp)Ru(η6-biphenyl)](PF6) (1), [(η5-Cp)Ru(η6-terphenyl)](PF6) (3) and [(η5-Cp)2Ru(η6-terphenyl)](PF6)2 (4) was determined by X-ray single crystal methods. The interaction of the complexes [(η5-Cp)Ru(η6-quaterphenyl)]Cl, (6)Cl, and [(η5-Cp)2Ru(η6-quaterphenyl)]Cl2, (7)Cl2, with the DNA duplex d(5'-CGCGAATTCGCG-3')2 was studied using NMR techniques. The results showed that both complexes interacted non-specifically with both the minor and major grooves of the helix. Specifically, (6)Cl exhibited partial binding through intercalation between the T7 and T8 bases of the sequence without disrupting the C-G and A-T hydrogen bonds. Fluorometric determination of the complexes' binding constants revealed a significant influence of the number of connected phenyl rings in the paraphenylene ligand (L) on the binding affinity of their complexes with the d(5'-CGCGAATTCGCG-3')2. The complexes (6)Cl and (7)Cl2 were found to be highly cytotoxic against the A549 lung cancer cell line, with complex (6) being more effective than (7) (IC50 for (6)Cl: 17.45 ± 2.1 μΜ, IC50 for (7)Cl2: 65.83 ± 1.8 μΜ) and with a selectivity index (SI) (SI for (6)Cl: 1.1 and SI for (7)Cl2: 4.8).

Suicide gene delivery by morphology-adaptable enantiomeric peptide assemblies for combined ovarian cancer therapy

Suicide gene therapy is a promising therapeutic model for ovarian cancer (OC), while suffering from poor gene delivery and limited therapeutic efficacy. To address this concern, here we reported the GSH-responsive morphology-transformable enantiomeric peptide assemblies as delivering vehicles for suicide genes and co-delivery of paclitaxel (PTX). Connecting a lipid-like amphiphile and a hydrophilic arginine segment through disulfide bonds led to the enantiomeric peptides. The enantiomeric peptide assemblies are able to simultaneously uptake plasmid DNA (pDNA) and PTX based on electrostatic and hydrophobic interactions. The resulting co-assemblies underwent GSH-responsive disulfide cleavage and thereby promoting their assembly from nanoparticles to nanofibers, leading to the co-release of pDNA and PTX. Cellular and animal studies confirmed the co-delivery of pDNA and PTX into OC cells and the cell apoptosis by the enantiomeric peptides. In addition, in vitro and in vivo experiments supported the advanced uptake and cytotoxicity for L-type peptide vehicles by OC cells, and their great potential for OC-imaging, growth-inhibition and apoptosis-induction compared to D-counterpart. Our results demonstrate that the GSH-responsive morphology-transformable chiral peptide assemblies accurately and simultaneously release suicide genes and chemodrugs at tumor sites, thus providing a new strategy for the development of delivering vehicles for suicide gene and establishment of new therapeutic models for ovarian cancer. Statement of significanceAppropriate delivery carriers are essential for the clinical translation of cancer gene therapy, including the emerging suicide gene therapy. By combining the advantages of morphological transformable vehicles with the chirality peptides towards their bioactivity, we developed the GSH-responsive morphology-transformable enantiomeric peptide assemblies as delivering vehicles for suicide genes and co-delivery of paclitaxel. The GSH-responsive assembly of the enantiomeric peptides allows for precise release of plasmid DNA and paclitaxel in cancer cells, and promotes the formation of nanofibrils that facilitate gene entering nuclei for transfection. The enantiomeric peptide-based vehicles show the chirality-dependent capability for inducing cell apoptosis and inhibiting tumor growth. Our findings demonstrate a new strategy for developing therapeutic models for ovarian cancer.

Discovery of a far-red carbazole-benzoindolium fluorescent ligand that selectively targets mitochondrial DNA and suppresses breast cancer growth

G-quadruplex (G4) formation was considered to be more prevalent in the mitochondrial DNA (mtDNA) of cancer cells compared with normal cells. Stabilization of these G4s may induce mtDNA instability and cause mitochondrial dysfunction and subsequent cell death, which may be treated as a new strategy for cancer treatment. However, few ligands were developed to target mtG4s, leaving a huge room to improve. In this study, we designed and synthesized a series of carbazole-based ligands, among which, BKN-1 was identified as the most promising mitochondrial targeting fluorescent ligand with far-red emission. Then, we demonstrated that BKN-1 may robustly interact with mtG4s via a variety of biophysical, biological experiments. Subsequently, we proved that BKN-1 may cause mtDNA loss, disrupt mitochondrial integrity, decrease ATP level and trigger unbalanced ROS, thereby leading to apoptosis and autophagy. Finally, we verified that BKN-1 had good anti-tumor activity in both cellular and in vivo models. Altogether, this study provided a dual-function ligand that may not only track the formation of mtG4s but also induce mitochondrial dysfunction, which may be developed into an applicable chemical tool for investigating the structure and function of mtG4s, and moreover, an effective therapeutic agent for cancer interference.

Cancer cells possess different isotopic enrichment: Isotopic induced functionalizations of normal DNA mutations leading to cancer

Although the dynamics of telomeres during the life expectancy of normal cells has been extensively studied, there are still some unresolved issues regarding this research field. For example, the conditions required for telomere shortening leading to malignant transformations are not fully understood. In this work, we mass analyzed DNA of normal and cancer cells for comparing telomere isotopic compositions of white blood cells and cancer cells. We have found that the 1327 Da and 1672 Da characteristic telomere mass to charges cause differential mass distributions of about 1 Da among normal cells relative to cancer cells. These isotopic differences are consistent with a prior theory according to which replacing primordial, common isotopes of 1H, 12C, 14N, 16O, 24Mg, 31P and/or 32S by nonprimordial, uncommon isotopes of 2D, 13C, 15N, 17O, 25Mg and/or 33S leads to altered enzymatic dynamics. This replacement may subsequently modulate DNA and telomere codons resulting in transformation of normal cells to cancer cells (in 15 N depletion in telomeres dependent manner). The prior theory and the current data are consistent also with a recently observed non-uniform methylation pattern of the DNA of cancer cells relative to a more uniform methylation in the DNA of normal cells. We observe further evidence of nonprimordial isotopic accelerations of acetylations, methylations, hydroxylations and aminations of nucleosides with alterations of phosphorylations of nucleotides; which may explain the induction of mutations at the DNA, RNA and proteins leading to cancer and more general alterations of DNA, which are associated with aging. This difference in mass spectra between normal and cancer DNA may stem from different functionalizations and isotopic enrichments affecting the motion derived from nuclear magnetic moments (NMMs). We suggest that this phenomenon may lead to malignant transformation.

Inhibition of DHODH Enhances Replication-Associated Genomic Instability and Promotes Sensitivity in Endometrial Cancer.

Endometrial carcinoma (EC) is the most common gynecological malignancy in the United States. De novo pyrimidine synthesis pathways generate nucleotides that are required for DNA synthesis. Approximately 38% of human endometrial tumors present with an overexpression of human dihydroorotate dehydrogenase (DHODH). However, the role of DHODH in cancer cell DNA replication and its impact on modulating a treatment response is currently unknown. Here, we report that endometrial tumors with overexpression of DHODH are associated with a high mutation count and chromosomal instability. Furthermore, tumors with an overexpression of DHODH show significant co-occurrence with mutations in DNA replication polymerases, which result in a histologically high-grade endometrial tumor. An in vitro experiment demonstrated that the inhibition of DHODH in endometrial cancer cell lines significantly induced replication-associated DNA damage and hindered replication fork progression. Furthermore, endometrial cancer cells were sensitive to the DHODH inhibitor either alone or in combination with the Poly (ADP-ribose) polymerase 1 inhibitor. Our findings may have important clinical implications for utilizing DHODH as a potential target to enhance cytotoxicity in high-grade endometrial tumors.

Enhancement of Radiation Sensitivity by Cathepsin L Suppression in Colon Carcinoma Cells.

Cancer is one of the main causes of death globally. Radiotherapy/Radiation therapy (RT) is one of the most common and effective cancer treatments. RT utilizes high-energy radiation to damage the DNA of cancer cells, leading to their death or impairing their proliferation. However, radiation resistance remains a significant challenge in cancer treatment, limiting its efficacy. Emerging evidence suggests that cathepsin L (cath L) contributes to radiation resistance through multiple mechanisms. In this study, we investigated the role of cath L, a member of the cysteine cathepsins (caths) in radiation sensitivity, and the potential reduction in radiation resistance by using the specific cath L inhibitor (Z-FY(tBu)DMK) or by knocking out cath L with CRISPR/Cas9 in colon carcinoma cells (caco-2). Cells were treated with different doses of radiation (2, 4, 6, 8, and 10), dose rate 3 Gy/min. In addition, the study conducted protein expression analysis by western blot and immunofluorescence assay, cytotoxicity MTT, and apoptosis assays. The results demonstrated that cath L was upregulated in response to radiation treatment, compared to non-irradiated cells. In addition, inhibiting or knocking out cath L led to increased radiosensitivity in contrast to the negative control group. This may indicate a reduced ability of cancer cells to recover from radiation-induced DNA damage, resulting in enhanced cell death. These findings highlight the possibility of targeting cath L as a therapeutic strategy to enhance the effectiveness of RT. Further studies are needed to elucidate the underlying molecular mechanisms and to assess the translational implications of cath L knockout in clinical settings. Ultimately, these findings may contribute to the development of novel treatment approaches for improving outcomes of RT in cancer patients.

Results from the Cohort-Expansion Stage of a Phase I Trial of Tinostamustine Monotherapy in Advanced Hodgkin Lymphoma (HL), Non-Hodgkin Lymphoma (NHL) and Multiple Myeloma (MM) (NCT02576496)

Background Tinostamustine, a novel alkylating deacetylase inhibitor, improves drug access to cancer cell DNA strands, breaks them and counteracts damage repair. Tinostamustine was well tolerated, with signals of efficacy, during the dose-escalation stage of a Phase I study in patients with relapsed/refractory (R/R) haematological malignancies (Zinzani et al. HemaSphere 2019;3(S1):102:PF300) and for patients with HL in the cohort-expansion stage (Ghesquières et al. Blood 2021;138(S1):2472; Sureda et al. Blood 2022;140(S1):3696). Aims We report safety and efficacy findings from patients with advanced haematological malignancies including HL, cutaneous T-cell lymphoma (CTCL), peripheral T-cell lymphoma (PTCL), T-cell prolymphocytic leukaemia (T-PLL) and MM treated with tinostamustine in the expansion cohorts of a Phase I study. Methods Patients with advanced haematological malignancies, for whom no standard treatment with proven clinical benefit was available or recommended, were recruited to receive the recommended Phase II dose of tinostamustine. Patients with HL must have received ≥2 lines of prior therapy, CTCL 1-4 prior standard systemic therapies, PTCL >1 prior line of combination therapy, T-PLL ≥1 prior line of therapy and MM ≥1 prior systemic therapy. Adverse events (AEs) were assessed for severity using US National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE; version 4.03, June 2010; for QTc prolongations CTCAE version 5.0 was used). Treatment-related AEs, fatal AEs, serious adverse events (SAEs), and AEs resulting in trial discontinuation were recorded. Primary efficacy objectives were to estimate the overall response rate (ORR; complete response [CR] + partial response [PR]) and clinical benefit rate (CBR; CR + PR + stable disease ≥4 cycles [SD]) for each cohort and to evaluate the safety of tinostamustine. Secondary efficacy variables included progression-free survival (PFS) and overall survival (OS); all outcomes were evaluated from Cycle 3 until progression or toxicity. Results 48 patients with advanced haematological malignancies were enrolled to the study and received treatment with tinostamustine (HL, n=20; CTCL, n=13; PTCL, n=8; T-PLL, n=1; MM, n=6; Table). Patients with HL, CTCL, PTCL and T-PLL received 50 mg/m 2 (1 patient), 80 mg/m 2 (7 patients) and 100 mg/m 2 (34 patients) over 60 minutes on Day 1 of a 21-day cycle; patients with MM: 60 mg/m 2 over 60 minutes on Day 1 and Day 15 of a 28-day cycle. Patients received a median of 3.5 (range 1-12) cycles of tinostamustine. No unexpected AEs were observed. Treatment-emergent AEs (TEAEs) occurred in 46/48 (95.8%) patients (500 events), with 28 patients experiencing 90 events ≥Grade 3. Gastrointestinal AEs were observed in 33/48 patients, the majority of which were nausea or vomiting. Haematological AEs, including thrombocytopenia, anaemia and neutropenia, occurred in 27/48 patients. Serious TEAEs considered related to tinostamustine occurred in 11 patients with HL or CTCL ( Table) and included thrombocytopenia (n=3) and infusion-related reaction (n=1); one patient with CTCL experienced a fatal TEAE of decreased appetite. Overall, 22/48 (45.8%) patients discontinued due to progressive disease and 13/48 (21.6%) discontinued due to AEs. In the 46 patients included in the efficacy analysis, ORR was 30.4% (95% confidence interval [CI]: 17.7%, 45.8%) and CBR 52.2% (95% CI: 36.9%, 67.1%). 4 patients achieved a CR (2 patients with HL, 2 CTCL), 10 a PR (5 HL, 4 CTCL, 1 PTCL) and 14 SD (4 HL, 4 CTCL, 3 PTCL, 3 MM). Median PFS was 4.3 months (95% CI: 2.7, 6.6 months; HL, 3.8 [2.2, 9.4] months; CTCL, 7.3 [3.2, not estimable (NE)] months; PTCL, 2.6 [1.4, NE] months; T-PLL, 0.5 [NE, NE] months; MM, 2.4 [1.4, NE] months;). Median OS was 10.3 (95% CI: 2.2, NE) months for PTCL, 5.6 (95% CI: NE, NE) months for T-PLL and not estimable for HL, CTCL and MM. Conclusions Results from expansion cohorts further demonstrate that tinostamustine has manageable tolerability in patients with advanced haematological malignancies with no unexpected AEs. The principal TEAEs were haematological and gastrointestinal. An ORR of 30.4% and a median progression-free survival of 4.3 months were observed, revealing signals of efficacy in this heavily pre-treated patient population for whom no other standard therapy with proven clinical benefit was available or recommended. Funding: Mundipharma Research Limited and Purdue Pharma, LP

Results from the Cohort Expansion Stage of a Phase I Trial of Tinostamustine Monotherapy in Advanced Haematological Malignancies (NCT02576496): Findings from a Subset of Patients with Cutaneous T-Cell Lymphoma (CTCL)

Background Tinostamustine, a novel alkylating deacetylase inhibitor, improves drug access to cancer cell DNA strands, breaks them and counteracts damage repair. Tinostamustine was well tolerated, with signals of efficacy, during the dose-escalation stage of a Phase I study in patients with relapsed/refractory (R/R) haematological malignancies for whom no standard treatment with proven clinical benefit was available or recommended. Aims Here we report safety and efficacy findings for tinostamustine in an expansion cohort of patients with CTCL from the Phase I study in patients with advanced haematological malignancies. Methods Patients with advanced CTCL (either mycosis fungoides [MF] or Sezary syndrome [SS]), for whom no standard treatment with proven clinical benefit was available or recommended, received the recommended Phase II dose (RP2D) of tinostamustine 80 mg/m 2 (2 patients) and 100 mg/m 2 (11 patients) over 60 minutes on Day 1 of a 21-day cycle. Patients with CTCL who had received ≥1-4 prior standard systemic therapies were eligible to be enrolled into the cohort. Primary objectives included evaluation of overall response and the safety of tinostamustine. Adverse events (AEs) were assessed for severity using US National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events (CTCAE; version 4.03, June 2010) with the exception that assessment of QTc prolongations was based on CTCAE version 5.0. Treatment-related AEs, AEs leading to death, serious adverse events (SAEs), and AEs resulting in trial discontinuation were recorded. Efficacy objectives estimated the overall response rate (ORR; complete response [CR] + partial response [PR]) and clinical benefit rate (CBR; CR + PR + stable disease ≥4 cycles [SD]) of tinostamustine in patients with CTCL. Secondary efficacy variables included progression-free survival (PFS) and overall survival (OS); all outcomes were evaluated from Cycle 3 until progression or toxicity. Results Out of 48 patients with advanced haematological malignancies treated in the expansion-cohort stage of this Phase I study, 13 had CTCL (MF, n=9; SS, n=4; Table). Mean ± standard deviation age was 63.7 ± 12.9 years, 7/13 (53.8%) patients were female and over half of patients had an Eastern Cooperative Oncology Group performance status score of 0. At the end of the study, patients with CTCL had received a median of 5.0 (range 1-8) cycles of tinostamustine. No unexpected AEs were observed following tinostamustine treatment. Treatment-emergent adverse events (TEAEs) occurred in 12/13 (92.3%) patients. Gastrointestinal AEs were observed in 9/13 patients, the majority of which were nausea or vomiting. Haematological AEs, including thrombocytopenia and anaemia, occurred in 8/13 patients. Eleven serious TEAE events that were considered related to tinostamustine occurred in three patients ( Table) and included two events each of thrombocytopenia, neutropenia and leukopenia, and one event each of anaemia, lymphopenia, lichenoid keratosis, acute coronary syndrome, and interstitial lung disease. There were no incidences of QTcF >500 ms or increased >60 ms from baseline. Overall, 3/13 patients (23.1%) discontinued due to progressive disease and 5/13 (38.5%) due to AEs. One patient with MF experienced a fatal TEAE of decreased appetite. 12/13 patients in the safety analysis were evaluated for disease response. 2/12 patients achieved a CR (1 patient with MF, 1 with SS), 4/12 a PR (3 patients with MF, 1 with SS) and 4/12 experienced SD (2 patients with MF, 2 with SS). ORR was 50% (6/12 patients; 95% confidence interval [CI]: 21.1%, 78.9%) and CBR 83.3% (10/12 patients; 95% CI: 51.6%, 97.9%). Median PFS was 7.3 months (95% CI: 3.2, NE months; 6/12 patients progressed) and median OS was not estimable (4/12 patients died). Conclusions Initial results from this expansion cohort of patients with CTCL further demonstrate signals of efficacy in this heavily pre-treated patient population for whom no other standard therapy with proven clinical benefit was available or recommended; an ORR of 50%, with 6/12 patients achieving a CR or PR, and a median progression-free survival of 7.3 months were observed. Tinostamustine was well tolerated, with no unexpected AEs. The principal TEAEs were haematological and gastrointestinal. Funding: Mundipharma Research Limited and Purdue Pharma, LP

Chitosan-PEI passivated carbon dots for plasmid DNA and miRNA-153 delivery in cancer cells

These days carbon dots have been developed for multiple biomedical applications. In the current study, the transfection potential of synthesized carbon dots from single biopolymers such as chitosan, PEI-2kDa, and PEI-25kDa (CS-CDs, PEI2-CDs, and PEI25-CDs) and by combining two biopolymers (CP2-CDs and CP25-CDs) through a bottom-up approach have been investigated. The characterization studies revealed successful synthesis of fluorescent, positively charged carbon dots <20 nm in size. Synthesized carbon dots formed a stable complex with plasmid DNA (EGFP-N1) and miRNA-153 that protected DNA/miRNA from serum-induced degradation. In-vitro cytotoxicity analysis revealed minimal cytotoxicity in cancer cell lines (A549 and MDA-MB-231). In-vitro transfection of EGFP-N1 plasmid DNA with PEI2-CDs, PEI25-CDs and CP25-CDs demonstrated that these CDs could strongly transfect A549 and MDA-MB-231 cells. The highest EGFP-N1 plasmid transfection efficiency was observed with PEI2-CDs at a weight ratio of 32:1. PEI25-CDs polyplex showed maximum transfection at a weight ratio of 8:1 in A549 at a weight ratio of 16:1 in MDA-MB-231 cells. CP25-CDs exhibited the highest transfection at a weight ratio of 16:1 in both cell lines. The in-vitro transfection of target miRNA, i.e., miR-153 in A549 and MDA-MB-231 cells with PEI2-CDs, PEI25-CDs, and CP25-CDs suggested successful transfer of miR-153 into cells which induced significant cell death in both cell lines. Importantly, CS-CDs and CP2-CDs could be tolerated by cells up to 200 μg/mL concentration, while PEI2-CDs, PEI25-CDs, and CP25-CDs showed non-cytotoxic behavior at low concentrations (25 μg/mL). Together, these results suggest that a combination of carbon dots synthesized from chitosan and PEI (CP25-CDs) could be a novel vector for transfection nucleic acids that can be utilized in cancer therapy.

The mechanism of antiproliferative activity of the oxaliplatin pyrophosphate derivative involves its binding to nuclear DNA in cancer cells.

(1R,2R-diaminocyclohexane)(dihydropyrophosphato) platinum(II), also abbreviated as RRD2, belongs to a class of potent antitumor platinum cytostatics called phosphaplatins. Curiously, several published studies have suggested significant mechanistic differences between phosphaplatins and conventional platinum antitumor drugs. Controversial findings have been published regarding the role of RRD2 binding to DNA in the mechanism of its antiproliferative activity in cancer cells. This prompted us to perform detailed studies to confirm or rule out the role of RRD2 binding to DNA in its antiproliferative effect in cancer cells. Here, we show that RRD2 exhibits excellent antiproliferative activity in various cancer cell lines, with IC50 values in the low micromolar or submicromolar range. Moreover, the results of this study demonstrate that DNA lesions caused by RRD2 contribute to killing cancer cells treated with this phosphaplatin derivative. Additionally, our data indicate that RRD2 accumulates in cancer cells but to a lesser extent than cisplatin. On the other hand, the efficiency of cisplatin and RRD2, after they accumulate in cancer cells, in binding to nuclear DNA is similar. Our results also show that RRD2 in the medium, in which the cells were cultured before RRD2 accumulated inside the cells, remained intact. This result is consistent with the view that RRD2 is activated by releasing free pyrophosphate only in the environment of cancer cells, thereby allowing RRD2 to bind to nuclear DNA.

DNA templated Click Chemistry via 5-vinyl-2′-deoxyuridine and an acridine-tetrazine conjugate induces DNA damage and apoptosis in cancer cells

AimsClick Chemistry is providing valuable tools to biomedical research, but its direct use in therapies remains nearly unexplored. For cancer treatment, nucleoside analogues (NA) such as 5-vinyl-2′-deoxyuridine (VdU) can be metabolically incorporated into cancer cell DNA and subsequently “clicked” to form a toxic product. The inverse electron-demand Diels-Alder (IEDDA) reaction between VdU and an acridine-tetrazine conjugate (PINK) has previously been used to label cell nuclei of cultured cells. Here, we report tandem usage of VdU and PINK to induce cytotoxicity. Main methodsCell lines were subsequently treated with VdU and PINK, and cell viability was measured via well confluency and 3D tumor spheroid assays. DNA damage and apoptosis were evaluated using Western Blotting and cell cycle analysis by flow cytometry. Double stranded DNA break (DSB) formation was measured using the comet assay. Apoptosis was assessed by fluorescent detection of externalized phosphatidylserine residues. Key findingsWe report that the combination of VdU and PINK synergistically induces cytotoxicity in cultured human cells. The combination of VdU and PINK strongly reduced cell viability in 2D and 3D cultured cancer cells. Mechanistically, the compounds induced DNA damage through DSB formation, which leads to S-phase accumulation and apoptosis. SignificanceThe combination of VdU and PINK represents a novel and promising DNA-templated “click” approach for cancer treatment via selective induction of DNA damage.

Development of Transition Edge Sensors for the Detection of Secondary Electrons

Secondary electrons generated when carbon ions go through the body are considered to be playing a major role in damaging the DNA of cancerous cells. To fully understand the mechanism of carbon ions, experimental and quantitative analysis on the energy and the behavior of these electrons are important. Therefore, we have started the development of TES arrays for the detection of secondary electrons. By performing simulations using Geant4, we have confirmed that the superconducting thin film of a TES is able to stop the electrons. We have also found that relatively high energy secondary electrons might have an influence on the energy spectrum of electrons having energies lower than 100 eV. We are currently fabricating a prototype 2-pixel TES array for the detection of electrons.

A Cross-Talk about Radioresistance in Lung Cancer-How to Improve Radiosensitivity According to Chinese Medicine and Medicaments That Commonly Occur in Pharmacies.

Lung cancer is one of the most common cancers in the population and is characterized by non-specific symptoms that delay the diagnosis and reduce the effectiveness of oncological treatment. Due to the difficult placement of the tumor, one of the main methods of lung cancer treatment is radiotherapy, which damages the DNA of cancer cells, inducing their apoptosis. However, resistance to ionizing radiation may develop during radiotherapy cycles, leading to an increase in the number of DNA points of control that protect cells from apoptosis. Cancer stem cells are essential for radioresistance, and due to their ability to undergo epithelial-mesenchymal transition, they modify the phenotype, bypassing the genotoxic effect of radiotherapy. It is therefore necessary to search for new methods that could improve the cytotoxic effect of cells through new mechanisms of action. Chinese medicine, with several thousand years of tradition, offers a wide range of possibilities in the search for compounds that could be used in conventional medicine. This review introduces the potential candidates that may present a radiosensitizing effect on lung cancer cells, breaking their radioresistance. Additionally, it includes candidates taken from conventional medicine-drugs commonly available in pharmacies, which may also be significant candidates.

Synergistic Effects of New Curcumin Analog (PAC) and Cisplatin on Oral Cancer Therapy.

Oral cancer has traditionally been treated with surgery, radiotherapy, chemotherapy, or a combination of these therapies. Although cisplatin, a chemotherapy drug, can effectively kill oral cancer cells by forming DNA adducts, its clinical use is limited due to adverse effects and chemo-resistance. Therefore, there is a need to develop new, targeted anticancer drugs to complement chemotherapy, allowing for reduced cisplatin doses and minimizing adverse effects. Recent studies have shown that 3,5-Bis (4-hydroxy-3-methoxybenzylidene)-N-methyl-4-piperidine (PAC), a new curcumin analog, possesses anticancer properties and could be considered a complementary or alternative therapy. In this study, we aimed to assess the potential complementary effects of PAC in combination with cisplatin for treating oral cancer. We conducted experiments using oral cancer cell lines (Ca9-22) treated with different concentrations of cisplatin (ranging from 0.1 μM to 1 μM), either alone or in conjunction with PAC (2.5 and 5 μM). Cell growth was measured using the MTT assay, while cell cytotoxicity was evaluated using an LDH assay. Propidium iodide and annexin V staining were employed to examine the impact on cell apoptosis. Flow cytometry was used to investigate the effects of the PAC/cisplatin combination on cancer cell autophagy, oxidative stress, and DNA damage. Additionally, a Western Blot analysis was performed to assess the influence of this combination on pro-carcinogenic proteins involved in various signaling pathways. The results demonstrated that PAC enhanced the efficacy of cisplatin in a dose-dependent manner, leading to a significant inhibition of oral cancer cell proliferation. Importantly, treatment with PAC (5 μM) alongside different concentrations of cisplatin reduced the IC50 of cisplatin tenfold. Combining these two agents increased apoptosis by further inducing caspase activity. In addition, the concomitant use of PAC and cisplatin enhances oral cancer cell autophagy, ROS, and MitoSOX production. However, combined PAC with cisplatin inhibits the mitochondrial membrane potential (ΔΨm), which is a marker for cell viability. Finally, this combination further enhances the inhibition of oral cancer cell migration via the inhibition of epithelial-to-mesenchymal transition genes, such as E-cadherin. We demonstrated that the combination of PAC and cisplatin markedly enhanced oral cancer cell death by inducing apoptosis, autophagy, and oxidative stress. The data presented indicate that PAC has the potential to serve as a powerful complementary agent to cisplatin in the treatment of gingival squamous cell carcinomas.

Machine learning immune-related gene based on KLRB1 model for predicting the prognosis and immune cell infiltration of breast cancer.

Breast cancer is a prevalent malignancy that predominantly affects women. The development and progression of this disease are strongly influenced by the tumor microenvironment and immune infiltration. Therefore, investigating immune-related genes associated with breast cancer prognosis is a crucial approach to enhance the diagnosis and treatment of breast cancer. We analyzed data from the TCGA database to determine the proportion of invasive immune cells, immune components, and matrix components in breast cancer patients. Using this data, we constructed a risk prediction model to predict breast cancer prognosis and evaluated the correlation between KLRB1 expression and clinicopathological features and immune invasion. Additionally, we investigated the role of KLRB1 in breast cancer using various experimental techniques including real-time quantitative PCR, MTT assays, Transwell assays, Wound healing assays, EdU assays, and flow cytometry. The functional enrichment analysis of immune and stromal components in breast cancer revealed that T cell activation, differentiation, and regulation, as well as lymphocyte differentiation and regulation, play critical roles in determining the status of the tumor microenvironment. These DEGs are therefore considered key factors affecting TME status. Additionally, immune-related gene risk models were constructed and found to be effective predictors of breast cancer prognosis. Further analysis through KM survival analysis and univariate and multivariate Cox regression analysis demonstrated that KLRB1 is an independent prognostic factor for breast cancer. KLRB1 is closely associated with immunoinfiltrating cells. Finally, in vitro experiments confirmed that overexpression of KLRB1 inhibits breast cancer cell proliferation, migration, invasion, and DNA replication ability. KLRB1 was also found to inhibit the proliferation of breast cancer cells by blocking cell division in the G1/M phase. KLRB1 may be a potential prognostic marker and therapeutic target associated with the microenzymic environment of breast cancer tumors, providing a new direction for breast cancer treatment.

Investigating the intermolecular interactions in the explicitly solvated complexes of lomustine with water and ethanol

Lomustine is an alkylating chemotherapy drug that is used to treat diverse types of cancer, including brain tumors, Hodgkin's lymphoma, and non-Hodgkin's lymphoma, which works by interfering with the DNA in cancer cells, preventing them from dividing and growing. As such the lipid bilayer of the cell and body fluids provides the environments in which lomustine (lmt) performs its biological function. Chemical reactions involving biological systems occur in the liquid phase, where accurate modeling of the reaction pathways considers the influence of the solvent used. Implicit solvation adequately accounts for these effects but falls short when evaluating solvent-solute interactions. This study aims to explore the structures, thermodynamics, reactivity, UV–vis spectroscopy, energy decomposition analysis, and the interaction energies of lmt with molecules of water and ethanol (n = 1, 2, and 3), using density functional theory (DFT) at the ωB97XD/6–311++G (d, p) level of theory. The thermodynamics results reveal that the polarity of water molecules significantly influences the interaction strength of the studied systems as the interaction observed between lmt with W1, Et1, and Et2 is feasible and spontaneous, compared to others. The stability of the different clusters depends on the intermolecular hydrogen bonds formed between the drug and the polar solvent as explicated by the H-bond interaction distance. Also, the interaction of lmt with each of the solvents causes a slight deformation in the geometry of the lmt, moreover, the reactivity descriptors predicted the interaction of lmt to increase with a corresponding increase in the addition of water molecules.

Palm Fruit (Phoenix dactylifera L.) Pollen Extract Inhibits Cancer Cell and Enzyme Activities and DNA and Protein Damage.

Palm fruit pollen extract (PFPE) is a natural source of bioactive polyphenols. The primary aim of the study was to determine the antioxidant, antimicrobial, anticancer, enzyme inhibition, bovine serum albumin (BSA), and DNA-protective properties of PFPE and identify and quantify the phenolic compounds present in PFPE. The results demonstrated that PFPE exhibited potent antioxidant activity in various radical-scavenging assays, including (2,2-diphenyl-1-picrylhydrazyl) (DPPH•), 2,2-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS•), nitric oxide (NO), ferric-reducing/antioxidant power (FRAP), and total antioxidant capacity (TAC). PFPE also displayed antimicrobial activity against several pathogenic bacteria. Similarly, PFPE reduced acetylcholinesterase, tyrosinase, and α-amylase activities. PFPE has been proven to have an anticancer effect against colon carcinoma (Caco-2), hepatoma (HepG-2), and breast carcinoma (MDA) cancer cells. Apoptosis occurred in PFPE-treated cells in a dose-dependent manner, and cell cycle arrest was observed. Furthermore, in breast cancer cells, PFPE down-regulated Bcl-2 and p21 and up-regulated p53 and Caspase-9. These results show that PFPE constitutes a potential source of polyphenols for pharmaceutical, nutraceutical, and functional food applications.

Suppressing cancer by damaging cancer cell DNA using LED irradiation.

High-energy irradiation eliminates cancer cells by destroying their genetic components. However, there are several side effects from doing this, such as fatigue, dermatitis, and hair loss, which remain obstacles to this treatment. Here, we propose a moderate method that uses low-energy white light from a light-emitting diode (LED) to selectively inhibit cancer cell proliferation without affecting normal cells. The association between LED irradiation and cancer cell growth arrest was evaluated based on cell proliferation, viability, and apoptotic activity. Immunofluorescence, polymerase chain reaction, and western blotting were performed in vitro and in vivo to identify the metabolism related to the inhibition of HeLa cell proliferation. LED irradiation aggravated the defective p53 signaling pathway and induced cell growth arrest in cancer cells. Consequently, cancer cell apoptosis was induced by the increased DNA damage. Additionally, LED irradiation inhibited the proliferation of cancer cells by suppressing the MAPK pathway. Furthermore, the suppression of cancer growth by the regulation of p53 and MAPK was observed in cancer-bearing mice irradiated with LED. Our findings suggest that LED irradiation can suppress cancer cell activity and may contribute to preventing the proliferation of cancer cells after medical surgery without causing side effects.

Multicomponent metal-organic framework nanocomposites for tumor-responsive synergistic therapy

Targeted tumor therapy through tumor microenvironment (TME)-responsive nanoplatforms is an emerging treatment strategy used to enhance tumor-specificity to selectively kill cancer cells. Here, we introduce a nanosized zeolitic imidazolate framework-8 (ZIF-8) that simultaneously contains natural glucose oxidase (GOx) and Prussian blue nanoparticles (PBNPs) to construct multi-component metal-organic framework nanocomposites (denoted as ZIF@GOx@PBNPs), which possess cascade catalytic activity selectively within the TME. Once reaching a tumor site, GOx and PBNPs inside the nanocomposites are sequentially released and participate in the cascade catalytic reaction. In weak acidic TME, GOx, which effectively catalyzes the oxidation of intratumoral glucose to hydrogen peroxide (H2O2) and gluconic acid, not only initiates starvation therapy by cutting off the nutrition source for cancer cells but also produces the reactant for sequential Fenton reaction for chemodynamic therapy. Meanwhile, PBNPs, which are released from the ZIF-8 framework dissociated by acidified pH due to the produced gluconic acid, convert the generated H2O2 into harmful radicals to melanomas. In this way, the cascade catalytic reactions of ZIF@GOx@PBNPs enhance reactive oxygen species production and cause oxidative damage to DNA in cancer cells, resulting in remarkable inhibition of tumor growth. The tumor specificity is endowed by using the biomolecules overexpressed in TME as a “switch” to initiate the first catalytic reaction by GOx. Given the significant antitumor efficiency both in vitro and in vivo, ZIF@GOx@PBNPs could be applied as a promising therapeutic platform enabling starvation/chemodynamic synergism, high therapeutic efficiency, and minimal side effects.

Parallel sequencing of extrachromosomal circular DNAs and transcriptomes in single cancer cells

Extrachromosomal DNAs (ecDNAs) are common in cancer, but many questions about their origin, structural dynamics and impact on intratumor heterogeneity are still unresolved. Here we describe single-cell extrachromosomal circular DNA and transcriptome sequencing (scEC&T-seq), a method for parallel sequencing of circular DNAs and full-length mRNA from single cells. By applying scEC&T-seq to cancer cells, we describe intercellular differences in ecDNA content while investigating their structural heterogeneity and transcriptional impact. Oncogene-containing ecDNAs were clonally present in cancer cells and drove intercellular oncogene expression differences. In contrast, other small circular DNAs were exclusive to individual cells, indicating differences in their selection and propagation. Intercellular differences in ecDNA structure pointed to circular recombination as a mechanism of ecDNA evolution. These results demonstrate scEC&T-seq as an approach to systematically characterize both small and large circular DNA in cancer cells, which will facilitate the analysis of these DNA elements in cancer and beyond.