Optical Imaging of Cancer-Related Proteases Using Near-Infrared Fluorescence Matrix Metalloproteinase-Sensitive and Cathepsin B-Sensitive Probes

Cathepsin B and matrix metalloproteinase (MMP) play key roles in tumor progression by controlled degradation of extracellular matrix. Consequently, these proteases have been attracted in cancer research, and many imaging probes utilizing these proteases have been developed. Our groups developed cathepsin B and MMP imaging nanoprobes based on polymer nanoparticle platform. Both cathepsin B and MMP imaging probes used near-infrared fluorescence (NIRF) dye and dark-quencher to for high sensitivity, and protease-sensitive peptide sequence in each probe authorized high specificity of the probes. We compared the bioactivities of cathepsin B and MMP sensitive probes in cancer-related environments to investigate the biological property of the probes. As a result, cathepsin B probe showed fluorescence recovery after the probe entered the cytoplasm. This property could be useful to evaluate the cytoplasmic targeted delivery by using probe-conjugated nanoparticles in vivo. On the other hand, MMP probe was superior in specificity in vivo and tissue study. This comparative study will provide precise information about peptide-based optical probes, and allow their proper application to cancer diagnosis

Prognostic Value of p53 and bcl-2 Expression in Patients Treated with Breast Conservative Therapy

Prognostic value of p53 and bcl-2 expression on treatment outcome in breast cancer patients has been extensively evaluated, but the results were inconclusive. We evaluated the prognostic significance of these molecular markers in patients treated with breast conserving surgery and radiotherapy. One hundred patients whose immunostaining of p53 and bcl-2 expression was available among 125 patients who underwent radiotherapy after breast conserving surgery and axillary lymph node dissection were enrolled into this study. Eighty-seven patients also received adjuvant chemotherapy and/or hormonal therapy. Conventional clinicopathologic variables and treatment-related factors were also considered. The 5-yr loco-regional relapse-free and distant metastasis-free survival rates were 91.7% and 90.9%, respectively. On univariate analysis, age, T stage and the absence of bcl-2 & estrogen receptor (ER) expression were associated with loco-regional relapse-free survival. When incorporating these variables into Cox proportional hazard model, only bcl-2(-)/ER(-) phenotype was an adverse prognostic factor (P=0.018). As for the distant metastasis-free survival, age, T stage, and p53 expression were significant on univariate analysis. However, p53 expression was the only prognosticator on multivariate analysis (P=0.009). A bcl-2(-)/ER(-) phenotype and p53 expression are useful molecular markers predicting loco-regional relapse-free and distant metastasis-free survival, respectively, in patients treated with breast conserving surgery and radiotherapy

Anti-tumor effects of rivoceranib against canine melanoma and mammary gland tumour in vitro and in vivo mouse xenograft models

Background Rivoceranib, a novel tyrosine kinase inhibitor, exhibits anti-tumour effects by selectively blocking vascular endothelial growth factor receptor-2 (VEGFR2) in cancer cells. Recently, the therapeutic effects of rivoceranib on solid tumours have been elucidated in human patients. However, the anti-tumour effects of rivoceranib against canine cancer remain unclear. Here, we investigated the anti-tumour effects of rivoceranib using in vitro and in vivo mouse xenograft models. Methods We performed cell proliferation, cell cycle, and migration assays to determine the effects of rivoceranib on canine solid tumour cell lines in vitro. Furthermore, apoptosis and angiogenesis in tumour tissues were examined using a TUNEL assay and immunohistochemistry methods with an anti-cluster of differentiation-31 antibody, respectively. Additionally, the expression levels of cyclin-D1 and VEGFR2 activity were determined using western blot analysis. Results Rivoceranib treatment showed anti-proliferative effects and mediated cell cycle arrest in the canine melanoma cell line (LMeC) and the mammary gland tumour (MGT) cell line (CHMp). In animal experiments, rivoceranib decreased the average volume of LMeC cells compared to that following control treatment, and similar results were observed in CHMp cells. Histologically, rivoceranib induced apoptosis and exerted an anti-angiogenic effect in tumour tissues. It also downregulated the expression of cyclin-D1 and inhibited VEGFR2 activity. Conclusion Our results show that rivoceranib inhibits proliferation and migration of tumour cells. These findings support the potential application of rivoceranib as a novel chemotherapeutic strategy for canine melanoma and MGTs.This research was supported by Basic Science Research Program to Research Institute for Basic Sciences (RIBS) of Jeju National University through the National Research Foundation of Korea (NRF) funded by the Ministry of Educa‑tion (2019R1A6A1A10072987)

Lapatinib, a Dual EGFR and HER2 Tyrosine Kinase Inhibitor, Downregulates Thymidylate Synthase by Inhibiting the Nuclear Translocation of EGFR and HER2

Epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) has been shown to exert a synergistic antitumor effect when combined with fluoropyrimidine. This synergy may be attributable to the downregulation of thymidylate synthase (TS), which is frequently overexpressed in fluoropyrimidine-resistant cancer cells. However, the molecular mechanism underlying the downregulation of TS has yet to be clearly elucidated.In this study, we demonstrate that lapatinib, a dual TKI of EGFR and HER2 downregulates TS via inhibition of the nuclear translocation of EGFR and HER2. From our cDNA microarray experiments, we determined that a variety of nucleotide synthesis-related genes, including TS, were downregulated with lapatinib, and this was apparent in HER2-amplified cells. Targeted and pharmacologic inhibition assays confirmed that the dual inhibition of EGFR and HER2 is required for the more effective reduction of TS as compared to what was observed with gefitinib or trasutuzumab alone. Additionally, we determined that co-transfected EGFR and HER2 activate the TS gene promoter more profoundly than do either EGFR or HER2 alone. The translocation of EGFR and HER2 into the nucleus and the subsequent activation of the TS promoter were inhibited by lapatinib.These results demonstrate that lapatinib inhibits the nuclear translocation of EGFR and HER2 and downregulates TS, thus sensitizing cancer cells to fluoropyrimidine

Prognostic value of low muscle mass at the 12th thoracic vertebral level in multiple myeloma treated with transplantation: CAREMM-2101 study

PURPOSEAutologous hematopoietic stem cell transplantation (ASCT) has been introduced as a standard treatment for newly diagnosed multiple myeloma (NDMM) following novel agent-based induction chemotherapy. This study investigated whether pre-ASCT low muscle mass evaluated using the paraspinal muscle index (PMI) at the 12th thoracic vertebra (T12) level is a reliable prognostic marker in NDMM after chemotherapy.METHODSA multi-center registry database was retrospectively analyzed. Between 2009 and 2020, 190 patients with chest computed tomography images underwent frontline ASCT following induction therapy. The PMI was defined as the value of the paraspinal muscle area at the T12 level divided by the square of the patient’s height. The cut-off value indicating a low muscle mass was sex-specific, using the lowest quintiles.RESULTSOf the 190 patients, 38 (20%) were in the low muscle mass group. The low muscle mass group had a lower 4-year overall survival (OS) rate than the non-low muscle mass group (68.5% vs. 81.2%; P = 0.074). The median progression-free survival (PFS) in the low muscle mass group was significantly shorter compared with the non-low muscle mass group (23.3 months vs. 29.2 months; P = 0.029). The cumulative incidence of transplant-related mortality (TRM) was significantly higher in the low muscle mass group than in the non-low muscle mass group (4-year probability of TRM incidence, 10.6% vs. 0.7%; P < 0.001). In contrast, no significant difference in the cumulative incidence of disease progression was found between the two groups. Multivariate analysis revealed that low muscle mass was associated with significant negative outcomes for OS [(hazard ratio (HR): 2.14; P = 0.047], PFS (HR: 1.78; P = 0.012), and TRM (HR: 12.05; P = 0.025).CONCLUSIONParaspinal muscle mass may have a prognostic role in NDMM patients who undergo ASCT. Patients with low paraspinal muscle mass have lower survival outcomes compared to non-low muscle mass group

Efficacy and Safety of Cabergoline as First Line Treatment for Invasive Giant Prolactinoma

Although cabergoline is effective in the treatment of micro- and macro-prolactinoma, little is known about its efficacy in the treatment of invasive giant prolactinoma. We investigated the efficacy and safety of cabergoline in 10 male patients with invasive giant prolactinoma. Before treatment, mean serum prolactin level was 11,426 ng/mL (range, 1,450-33,200 ng/mL) and mean maximum tumor diameter was 51 mm (range, 40-77 mm). Three months after initiation of cabergoline treatment, serum prolactin concentrations decreased more than 97% in 9 patients; at last follow-up (mean treatment duration, 19 months), the mean decrease in serum prolactin concentrations was 98%, with 5 patients having normal serum prolactin levels. At first MRI follow-up (3-12 months after initiation of cabergoline), the mean reduction in tumor size was 85±4% (range, 57-98%). Cabergoline treatment for more than 12 months caused a greater reduction in tumor size compared to the treatment for less than 12 months (97±1% vs. 78±7%, P<0.05). These findings indicate that cabergoline treatment led to a significant and rapid reduction in serum prolactin concentrations and tumor size in patients with giant prolactinoma. Therefore, cabergoline represents an effective and well-tolerated treatment for invasive giant prolactinoma

Direct Reprogramming of Rat Neural Precursor Cells and Fibroblasts into Pluripotent Stem Cells

Background: Given the usefulness of rats as an experimental system, an efficient method for generating rat induced pluripotent stem (iPS) cells would provide researchers with a powerful tool for studying human physiology and disease. Here, we report direct reprogramming of rat neural precursor (NP) cells and rat embryonic fibroblasts (REF) into iPS cells by retroviral transduction using either three (Oct3/4, Sox2, and Klf4), four (Oct3/4, Sox2, Klf4, and c-Myc), or five (Oct3/4, Sox2, Klf4, c-Myc, and Nanog) genes. Methodology and Principal Findings: iPS cells were generated from both NP and REF using only three (Oct3/4, Sox2, and Klf4) genes without c-Myc. Two factors were found to be critical for efficient derivation and maintenance of rat iPS cells: the use of rat instead of mouse feeders, and the use of small molecules specifically inhibiting mitogen-activated protein kinase and glycogen synthase kinase 3 pathways. In contrast, introduction of embryonic stem cell (ESC) extracts induced partial reprogramming, but failed to generate iPS cells. However, when combined with retroviral transduction, this method generated iPS cells with significantly higher efficiency. Morphology, gene expression, and epigenetic status confirmed that these rat iPS cells exhibited ESC-like properties, including the ability to differentiate into all three germ layers both in vitro and in teratomas. In particular, we found that these rat iPS cells could differentiate to midbrain-like dopamine neurons with a high efficiency. Conclusions/Significance: Given the usefulness of rats as an experimental system, our optimized method would be useful for generating rat iPS cells from diverse tissues and provide researchers with a powerful tool for studying human physiology and disease