Heat shock factor 1 inhibition enhances the effects of modulated electro hyperthermia in a triple negative breast cancer mouse model.

Female breast cancer is the most diagnosed cancer worldwide. Triple negative breast cancer (TNBC) is the most aggressive type and there is no existing endocrine or targeted therapy. Modulated electro-hyperthermia (mEHT) is a non-invasive complementary cancer therapy using an electromagnetic field generated by amplitude modulated 13.56 MHz frequency that induces tumor cell destruction. However, we have demonstrated a strong induction of the heat shock response (HSR) by mEHT, which can result in thermotolerance. We hypothesized that inhibition of the heat shock factor 1 (HSF1) can synergize with mEHT and enhance tumor cell-killing. Thus, we either knocked down the HSF1 gene with a CRISPR/Cas9 lentiviral construct or inhibited HSF1 with a specific small molecule inhibitor: KRIBB11 in vivo. Wild type or HSF1-knockdown 4T1 TNBC cells were inoculated into the mammary gland's fat pad of BALB/c mice. Four mEHT treatments were performed every second day and the tumor growth was followed by ultrasound and caliper. KRIBB11 was administrated intraperitoneally at 50 mg/kg daily for 8 days. HSF1 and Hsp70 expression were assessed. HSF1 knockdown sensitized transduced cancer cells to mEHT and reduced tumor growth. HSF1 mRNA expression was significantly reduced in the KO group when compared to the empty vector group, and consequently mEHT-induced Hsp70 mRNA upregulation diminished in the KO group. Immunohistochemistry (IHC) confirmed the inhibition of Hsp70 upregulation in mEHT HSF1-KO group. Demonstrating the translational potential of HSF1 inhibition, combined therapy of mEHT with KRIBB11 significantly reduced tumor mass compared to either monotherapy. Inhibition of Hsp70 upregulation by mEHT was also supported by qPCR and IHC. In conclusion, we suggest that mEHT-therapy combined with HSF1 inhibition can be a possible new strategy of TNBC treatment with great translational potential.

Correction to "Digoxin-Mediated Inhibition of Potential Hypoxia-Related Angiogenic Repair in Modulated Electro-Hyperthermia (mEHT)-Treated Murine Triple-Negative Breast Cancer Model".

[This corrects the article DOI: 10.1021/acsptsci.3c00296.].

Modulated Electro-Hyperthermia Accelerates Tumor Delivery and Improves Anticancer Activity of Doxorubicin Encapsulated in Lyso-Thermosensitive Liposomes in 4T1-Tumor-Bearing Mice.

Modulated electro-hyperthermia (mEHT) is an adjuvant cancer therapy that enables tumor-selective heating (+2.5 °C). In this study, we investigated whether mEHT accelerates the tumor-specific delivery of doxorubicin (DOX) from lyso-thermosensitive liposomal doxorubicin (LTLD) and improves its anticancer efficacy in mice bearing a triple-negative breast cancer cell line (4T1). The 4T1 cells were orthotopically injected into Balb/C mice, and mEHT was performed on days 9, 12, and 15 after the implantation. DOX, LTLD, or PEGylated liposomal DOX (PLD) were administered for comparison. The tumor size and DOX accumulation in the tumor were measured. The cleaved caspase-3 (cC3) and cell proliferation were evaluated by cC3 or Ki67 immunohistochemistry and Western blot. The LTLD+mEHT combination was more effective at inhibiting tumor growth than the free DOX and PLD, demonstrated by reductions in both the tumor volume and tumor weight. LTLD+mEHT resulted in the highest DOX accumulation in the tumor one hour after treatment. Tumor cell damage was associated with cC3 in the damaged area, and with a reduction in Ki67 in the living area. These changes were significantly the strongest in the LTLD+mEHT-treated tumors. The body weight loss was similar in all mice treated with any DOX formulation, suggesting no difference in toxicity. In conclusion, LTLD combined with mEHT represents a novel approach for DOX delivery into cancer tissue.

Digoxin-Mediated Inhibition of Potential Hypoxia-Related Angiogenic Repair in Modulated Electro-Hyperthermia (mEHT)-Treated Murine Triple-Negative Breast Cancer Model.

Triple-negative breast cancer (TNBC) is a highly aggressive breast cancer type with no targeted therapy and hence limited treatment options. Modulated electrohyperthermia (mEHT) is a novel complementary therapy where a 13.56 MHz radiofrequency current targets cancer cells selectively, inducing tumor damage by thermal and electromagnetic effects. We observed severe vascular damage in mEHT-treated tumors and investigated the potential synergism between mEHT and inhibition of tumor vasculature recovery in our TNBC mouse model. 4T1/4T07 isografts were orthotopically inoculated and treated three to five times with mEHT. mEHT induced vascular damage 4-12 h after treatment, leading to tissue hypoxia detected at 24 h. Hypoxia in treated tumors induced an angiogenic recovery 24 h after the last treatment. Administration of the cardiac glycoside digoxin with the potential hypoxia-inducible factor 1-α (HIF1-α) and angiogenesis inhibitory effects could synergistically augment mEHT-mediated tumor damage and reduce tissue hypoxia signaling and consequent vascular recovery in mEHT-treated TNBC tumors. Conclusively, repeated mEHT induced vascular damage and hypoxic stress in TNBC that promoted vascular recovery. Inhibiting this hypoxic stress signaling enhanced the effectiveness of mEHT and may potentially enhance other forms of cancer treatment.

Enhancing therapeutic efficacy in triple-negative breast cancer and melanoma: synergistic effects of modulated electro-hyperthermia (mEHT) with NSAIDs especially COX-2 inhibition in in vivo models.

Triple-negative breast cancer (TNBC) is a leading cause of cancer mortality and lacks modern therapy options. Modulated electro-hyperthermia (mEHT) is an adjuvant therapy with demonstrated clinical efficacy for the treatment of various cancer types. In this study, we report that mEHT monotherapy stimulated interleukin-1 beta (IL-1ß) and interleukin-6 (IL-6) expression, and consequently cyclooxygenase 2 (COX-2), which may favor a cancer-promoting tumor microenvironment. Thus, we combined mEHT with nonsteroid anti-inflammatory drugs (NSAIDs): a nonselective aspirin, or the selective COX-2 inhibitor SC236, in vivo. We demonstrate that NSAIDs synergistically increased the effect of mEHT in the 4T1 TNBC model. Moreover, the strongest tumor destruction ratio was observed in the combination SC236 + mEHT groups. Tumor damage was accompanied by a significant increase in cleaved caspase-3, suggesting that apoptosis played an important role. IL-1ß and COX-2 expression were significantly reduced by the combination therapies. In addition, a custom-made nanostring panel demonstrated significant upregulation of genes participating in the formation of the extracellular matrix. Similarly, in the B16F10 melanoma model, mEHT and aspirin synergistically reduced the number of melanoma nodules in the lungs. In conclusion, mEHT combined with a selective COX-2 inhibitor may offer a new therapeutic option in TNBC.

Novel dynamic stabilization method for medial instability of the first metatarsophalangeal joint.

Medial collateral ligament injury of the first metatarsophalangeal (MTP) joint is rare. If it is missed, chronic instability and traumatic hallux valgus develop, requiring surgical treatment. Different methods have been reported in the limited available literature aiming to restore the balance between the lateral and medial stabilizers by tightening the medial joint capsule with or without additional tendon graft. Our described method utilizes a suture button device (Mini TightRope, Arthrex, Naples, Florida) for reconstruction. This device applies tension to hold the hallux in the correct position, providing stability. Relevant diagnostic regimen, surgical technique, and postoperative care are described, along with a case of a handball player who underwent this procedure. He continues to perform at the same level 38 months postoperatively. Mini TightRope fixation for chronic medial first MTP instability has not been reported. It does not require postoperative immobilization and allows faster return to sport, so it seems superior to other methods when treating athletes.

Detection of gentamicin emission from bone cement in the early postoperative period following total hip arthroplasty.

This article describes the characteristics of gentamicin emission from the bone cement-antibiotic complex in the early postoperative period following total hip arthroplasty. Gentamicin levels of the drain fluid taken at 6, 24, and 48 hours postoperatively were measured with a fluorescent polarization immunoassay method. Mean gentamicin concentrations were 2.6, 1.2, and 0.6 mcg/mL, respectively. Age, sex, and body mass index had no significant influence on the outcome. Results showed that the amount of gentamicin in the wound fluid is inversely proportional to the total amount excreted. Twenty-four hours postoperatively, the average gentamicin concentrations in the drain fluid taken from around the endoprosthesis implanted with Palacos-R bone cement (Zimmer Warsaw, Ind), diminished, yet remained above the minimal inhibitory concentration level.

Examination of a novel, specified local antibiotic therapy through polymethylmethacrylate capsules in a rabbit osteomyelitis model.

Chronic bone and soft tissue suppurations have become more frequent recently due to the increasing number of high-energy injuries. There are certain antibiotic beads available for local administration, but they cannot always be applied specifically against the pyogenic microorganisms. In the present study, a new technique of local antibiotic therapy for the treatment of infections is described. Polymethylmethacrylate (PMMA) capsules were produced and filled with 0.1 ml Tazocin (0.02 g piperacillin sodium + 0.005 g tazobactam). The efficacy of these Tazocin-filled capsules was examined in vivo using a rabbit osteomyelitis model. Chronic osteomyelitis was induced in rabbit tibia by local injection of Staphylococcus aureus. The treatment included surgical debridement and implantation of Tazocin-containing PMMA capsules into the medullar cavity (n = 12). Simple surgical debridement with no antibiotic implantation was performed in control animals (n = 7). Results were evaluated using microbiological, radiological and histological methods 14 weeks after induction of osteomyelitis. Eight weeks after the implantation of PMMA capsules, complete physical, radiological and histological healing was achieved in 7 animals, initiation of the reparative phase was observed histologically in 3 cases and no reparative signs were detected in 2 rabbits. In the control group, no significant sign of reparation could be seen in any of the cases.

Comparative study of antibiotic-containing polymethylmetacrylate capsules and beads.

BACKGROUND: This study aimed at making local antibiotic therapy wider in cases of chronic suppurations by administering antibiotics which previously could not be given in this way through the conventional polymethylmetacrylate (PMMA) carrier techniques. Capsules from this material were produced with a pressing machine designed and laid out by us. The characteristics of antibiotic penetration from this novel carrier were compared to those of PMMA beads. METHODS: The time-dependent outflow of amikacin, clindamycin, pefloxacin, piperacillin + tazobactam, amoxicillin + clavulanic acid and cefotaxime was examined from the capsules and the beads with standard microbiological techniques using the Micrococcus luteus ATCC9341 test strain. The diameter of the inhibitory zones was measured after 24 h incubation at 37 degrees C and converted to mug/ml antibiotic concentrations. RESULTS AND CONCLUSIONS: Our results revealed that all antibiotics showed longer-lasting and higher concentration outflow from the PMMA capsules than from the beads. Therefore, these capsules can provide a more promising new opportunity for specific local antimicrobial treatment in cases of chronic suppurative bone and soft tissue injuries. In these cases the polymerization has already been completed and the heat does not influence the structure of the antibiotics; therefore, it can be inserted into the capsules in powder or solution form.

[The comparison of in vivo and in vitro elution of gentamycin from bone cement]. / Gentamicin csontcementbol történo in vivo és in vitro emissziójának összehasonlítása.

INTRODUCTION: The authors report their in vivo and in vitro results of the elution characteristics of gentamycin sulfate from bone cement, which is the most commonly used way of local antibiotic prophylaxis in Europe in the field of orthopedic surgery. AIM: The aim of this study was to investigate the elution of the gentamycin sulfate from bone cement, describe the dynamics of the emission in time and evaluate the relationship between the minimal inhibitory concentration (MIC) and the eluted concentration of the antibiotic. METHODS: The in vivo investigation samples were taken from 9 patient from drain fluids to evaluate the eluted antibiotic concentration by fluorescent polarisation immunoassay method (FPI). The in vitro emission-dynamics of two different bone cement-Gentamycin sulphate complex were analysed by plate diffusion method during one-year period after mixing. RESULTS: Their results showed that 24 hours after the operation the gentamycin concentrations in the drain fluid taken from around the endoprosthesis implanted with Palacos-R bone cement diminished, yet remained above the MIC level. High but rapidly decreasing antibiotic level was detected by the in vitro method within the first week, reading an almost steadily low concentration by the end of the first month. Surprisingly, after one year it was still possible to demonstrate the inhibitory effect of the drug from both tested types of cements. CONCLUSIONS: It is concluded that the gentamycin is able to elute from the bone cement in useful concentration after the implantation of endoprosthesis. However, this in vitro method is a useful and reproducible technique for the measurement of the efficacy of antibiotic emission from bone cement, the conversation of the results to the in vivo remains to be obscured. Nevertheless, the usage of local antibiotic prophylaxis seems to be useful during orthopaedic major intervention.