Publications by authors named "Robert Hoffman"

Background/aim: Metastatic prostate cancer is a recalcitrant disease. Our laboratory has previously treated prostate-cancer patients with methionine restriction effected by a low methionine diet and oral recombinant methioninase (o-rMETase), both alone and in combination with other agents. The present case is a 66-year-old patient who had a radical prostatectomy in 2019 with a Gleason score 3+3 and 3+4.

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Background/aim: For second-line chemotherapy of soft-tissue sarcoma, gemcitabine is administered in combination with docetaxel. However, more effective treatments are required for advanced soft-tissue sarcoma, where the efficacy is limited. The purpose of the present study was to compare the efficacy of rMETase and gemcitabine against HT1080 human fibrosarcoma cells and Hs27 normal fibroblasts, as well as to identify and effectively treat HT1080 cells that are resistant to gemcitabine associated with elevated c-MYC.

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Background/aim: Chronic lymphocytic leukemia (CLL) is currently incurable. CLL is characterized by disordered DNA methylation. The aim of the present study was to target methylation with methionine restriction in a patient with progressive CLL.

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Background/aim: Ifosfamide is used clinically with doxorubicin as first-line chemotherapy for soft-tissue sarcoma. However, ifosfamide efficacy for soft-tissue sarcoma is limited due to frequent occurence of ifosfamide resistance and thus more effective therapy is needed. The present study aimed to determine the synergy of recombinant methioninase (rMETase) plus ifosfamide against HT1080 human fibrosarcoma cells in vitro.

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Background/aim: Salmonella typhimurium A1-R (A1-R) targets and inhibits a wide range of cancer types without continuously infecting healthy tissue. Chloroquine, an antimalarial drug, induces apoptosis and inhibits autophagy in cancer cells. The aim of the present study was to determine the synergy of A1-R plus chloroquine on HT1080 human fibrosarcoma cells in vitro and in a nude-mouse model.

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Article Synopsis
  • Colorectal cancer is the third most common cancer, and managing unresectable metastatic cases, especially those with MSS and BRAF V600E mutation, poses significant challenges for treatment.
  • Two case reports illustrate the effectiveness of an alternating chemotherapy regimen (irinotecan and oxaliplatin along with capecitabine and bevacizumab) in two patients with MSS, BRAF V600E-mutated stage IV metastatic CRC, demonstrating a partial response and dropping carcinoembryonic antigen levels.
  • The study suggests that this alternating regimen offers a promising treatment strategy with improved progression-free survival compared to standard first-line therapies, making it a potential first-line option for patients with this specific type of colorectal cancer.
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Background/aim: Methionine addiction, known as the Hoffman effect, makes cancer cells more sensitive to methionine restriction than normal cells. However, the long-term effects of methionine restriction on cancer and normal cells have not been thoroughly studied.

Materials And Methods: HCT-116 human colorectal-cancer cells and Hs27 normal skin fibroblasts were treated with 0-8 U/ml of recombinant methioninase (rMETase) for 12 days.

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Background/aim: Ivermectin was initially utilized as a veterinary medication, demonstrating efficacy against various parasites. Pancreatic cancer is currently one of the most recalcitrant diseases. The aim of the present study was to demonstrate the synergy of the combination of recombinant methioninase (rMETase) and ivermectin to eradicate human pancreatic cancer cells in vitro.

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Background/aim: The Kaplan-Meier curves for patients treated with immune checkpoint inhibitors (ICIs) display a small group of potentially-cured patients with long-term survival, creating a 'kangaroo-tail' shape of the survival curve. However, the mechanistic basis of this phenomenon and what occurs in patients whose cancer is resistant to ICIs remain unclear. The present study aimed to answer these questions.

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Aim: This study investigates the impact of sub-toxic cisplatin levels on nuclear and nucleolar abnormalities and chromosome instability in HeLa cells since our current knowledge of cisplatin effects on these parameters is based on studies with high concentrations of cisplatin.

Materials And Methods: HeLa cells were exposed to gradually increasing sub-toxic doses of cisplatin (0.01 to 0.

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Nestin-expressing hair-follicle-associated pluripotent (HAP) stem cells from mouse and human have been shown to differentiate into neurons, glia, keratinocytes, smooth muscle cells, cardiac muscle cells, and melanocytes in vitro. HAP stem cells have promoted the recovery of peripheral nerve and spinal cord injuries in mouse models by differentiating into glial fibrillary acidic protein (GFAP)-positive Schwann cells. HAP stem cells enclosed on polyvinylidene fluoride membranes (PFM) were transplanted into the severed thoracic spinal cord of nude mice.

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Background: Kallmann syndrome (KS) is a rare genetic disorder marked by hypogonadotropic hypogonadism and either anosmia or hyposmia. It exhibits genetic heterogeneity, with mutations identified in only 30 % of cases, involving various genes such as KAL1, FGFR1, FGF8, CHD7, and SOX10. Here, we present a case of gonadotropin deficiency associated with KS, observed in both a mother and her daughter, the latter conceived through assisted reproductive technology using the mother's ovum.

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Inflammatory breast cancer (IBC) is characterized by numerous tumor emboli within lymphatics. In a recent study, we observed tumor embolic budding both in vitro and in vivo within lymphovascular spaces and proposed this to account for the plethora of tumor emboli seen in IBC. These observations did not address, however, how lymphovascular invasion is initiated or the mechanisms involved.

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Introduction: Unfortunately, children are not spared from the devastating effects of the ongoing opioid epidemic. In rare cases, young children exposed to opioids present with unique neuroimaging findings affecting the white matter, reminiscent of what was once seen with diacetylmorphine (heroin)-associated leukoencephalopathy. This constellation of findings is termed the pediatric opioid use-associated neurotoxicity with cerebellar edema (POUNCE) syndrome.

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Background/aim: Docetaxel combined with gemcitabine is a second-line treatment for soft-tissue sarcoma; however, its effectiveness is limited because of docetaxel resistance. The objective of the present study was to determine the potential of recombinant methioninase (rMETase) to enhance the efficacy of docetaxel on high-docetaxel-resistant human fibrosarcoma cells in vitro.

Materials And Methods: Docetaxel-resistant HT1080 (DTR-HT1080) human fibrosarcoma cells were established by culturing them in by progressively increasing concentrations of docetaxel from 0.

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Article Synopsis
  • Salmonella typhimurium A1-R is a type of bacteria that can target and inhibit cancer growth in mice, and the study aims to find the optimal oral dose for treating human fibrosarcoma in a nude mouse model.
  • The research involved three mouse groups: a control group, one receiving 5×10 CFU of the bacteria, and another receiving a lower dose of 3.3×10 CFU, with tumor size and bacterial presence being measured over time.
  • Results showed that the 3.3×10 CFU dose effectively reduced the tumor size, while the 5×10 CFU dose did not have the same effect, indicating dosage is critical for the therapeutic impact of the bacteria.
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Background/aim: Docetaxel combined with gemcitabine is a second-line therapy for osteosarcoma, but its efficacy is limited by the development of docetaxel resistance. The aim of the present study was to determine whether recombinant methioninase (rMETase) could reverse docetaxel resistance developed in osteosarcoma cells.

Materials And Methods: Docetaxel-resistant 143B (DTR-143B) osteosarcoma cells were established by treating the parental 143B cells to increasing docetaxel concentrations (0.

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Background/aim: Methionine restriction selectively arrests cancer cells during the S-phase of the cell cycle. We hypothesized that DNA damage may occur in S-phase in cancer cells during methionine restriction. To determine if this occurs, we used MiaPaCa-2 53BP1-green fluorescent protein (GFP) pancreatic cancer cells, which report GFP fluorescence in real time after DNA-damage response (DDR) in these cells.

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Article Synopsis
  • * Researchers analyzed serum samples from eight patients before and after surgery to quantify the levels of these exosomes using specialized beads.
  • * Findings indicated that levels of CD63 and CD9, as well as CD9 and HER2, decreased post-surgery in patients with HER2-positive tumors, suggesting these exosomes could be potential biomarkers for tracking tumor burden.
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Pancreatic cancer is the third leading cause of death related to cancer. The only possible cure presently is complete surgical resection; however, this is limited by difficulty in clearly defining tumor margins. Enhancement of the visualization of pancreatic ductal adenocarcinoma (PDAC) tumor margins using near-infrared dye-conjugated tumor-specific antibodies was pioneered by using anti-CEA, anti-CA19.

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Background: The present study aimed to validate the accuracy of a tumor-specific antibody to target liver metastases of colorectal cancer.

Methods: A humanized anti-CEA antibody conjugated to a fluorescent dye (M5A-IR800) was tested for targeting human colorectal cancer liver metastases (CRLMs) expressing luciferase in an orthotopic mouse model. Orthotopic mouse models of CRLMs were established by implanting fragments of a luciferase-expressing human colorectal cancer cell line, LS174T, in the liver of nude mice.

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  • Thyroid nodules in children and adolescents are rare but have a higher risk of cancer, prompting this study to assess the Thyroid Imaging Reporting and Data System (TI-RADS) for its effectiveness in predicting malignancy.
  • The study was a multi-institutional retrospective analysis of patients up to 21 years old with thyroid nodules from 2015 to 2020, comparing TI-RADS results with the American Thyroid Association's (ATA) size-based criteria for fine needle aspiration biopsy (FNAB).
  • Results showed that using TI-RADS criteria led to a significant reduction in FNAB recommendations (35.1% vs. 76.6% by ATA guidelines), while achieving high sensitivity in recognizing malignant nodules
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Background/aim: Methotrexate (MTX) resistance in osteosarcoma results in a very poor patient prognosis. We previously reported that super MTX-resistant osteosarcoma (143B-MTX) cells, selected from parental 143B osteosarcoma (143B-P) cells by culturing them with increasing concentrations of MTX, exhibited reduced malignancy, despite the over-expression of oncogenes. The present study explored the mechanism of reduced malignancy in the super MTX-resistant osteosarcoma cells.

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Article Synopsis
  • A 59-year-old man suffered from Western Gaboon viper (Bitis rhinoceros) envenomation, initially treated with North American crotalid antivenom, which proved ineffective.
  • He experienced worsening symptoms, including swelling and low platelet counts, prompting a transfer to a facility that provided South African Institute for Medical Research (SAIMR) polyvalent antivenom.
  • After receiving the appropriate antivenom, the patient's condition rapidly improved, demonstrating the importance of using species-specific antivenom for viper bites and consulting poison centers for proper treatment guidance.*
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