SLC4A4 is a novel driver of enzalutamide resistance in prostate cancer.

The androgen receptor signaling inhibitor (ARSI) enzalutamide (Enz) has shown critical efficacy in the treatment of advanced prostate cancer (PCa). However, the development of drug resistance is a significant factor contributing to mortality in PCa patients. We aimed to explore the key mechanisms of Enz-resistance. Through analysis of GEO databases, we identified SLC4A4 as a novel driver in Enz resistance. Long-term Enz treatment leads to the up-regulation of SLC4A4, which in turn mediates P53 lactylation via the NF-κB/STAT3/SLC4A4 axis, ultimately leading to the development of Enz resistance and progression of PCa. SLC4A4 knockdown overcomes Enz resistance both in vitro and in vivo. Hence, our results suggest that targeting SLC4A4 could be a promising therapeutic strategy for Enz resistance. STATEMENT OF SIGNIFICANCE: SLC4A4 is a novel driver of enzalutamide resistance.

Ipsilateral and contralateral patent processus vaginalis in pediatric patients with a unilateral nonpalpable testis.

This study aimed to investigate the incidence of patent processus vaginalis (PPV) in pediatric patients with a unilateral nonpalpable testis and explore the associated factors. From May 2014 to April 2017, 152 boys who were diagnosed with a unilateral nonpalpable testis and underwent laparoscopy in Shanghai Children's Hospital (Shanghai, China) were included in this study. The data were collected and reviewed, and the results were analyzed regarding the age at operation, side, development, and position of the nonpalpable testis. The mean age of the patients was 2.6 (standard deviation: 2.3) years. The testis was absent in 14 cases, nonviable in 81 cases, and viable in 57 cases. The incidence of PPV was 37.5% (57 of 152) on the ipsilateral side and 16.4% (25 of 152) on the contralateral side. The ipsilateral PPV was more prevalent when the nonpalpable testis occurred on the right side ( P < 0.01). Besides, patients with a viable testis had a greater incidence of ipsilateral PPV than those with a nonviable or absent testis ( P < 0.01). Moreover, this rate was the highest when the testis was in the abdominal cavity and the lowest when the testis was in the scrotum (both P < 0.01). However, the incidence of contralateral PPV was independent of all the factors. In conclusion, in children with a nonpalpable testis, the incidence of an ipsilateral PPV was significantly related to the side, development, and position of the testis, while it was independent of these factors on the contralateral side.

KRAS mutation status between left- and right-sided colorectal cancer: are there any differences in computed tomography?

PURPOSE: To investigate the differences in clinicopathological and imaging features according to KRAS mutation status in left- and right-sided colorectal cancer. METHOD: A total of 157 patients with pathologically proven colorectal cancer and preoperative contrast-enhanced multidetector CT examinations were enrolled. According to the tumor location and KRAS status, they were divided into two groups: the left-sided colorectal cancer (LCC) group (wild type, mutant type) and the right-sided colorectal cancer (RCC) group (wild type, mutant type). Clinicopathological and imaging features were recorded in each group. The imaging observation indicators included short axis diameter (SAD), longitudinal tumor length (LTL), tumor shape, pericolic fat stranding, bowel stenosis, intratumoral low-density range, enhancement pattern, and bowel obstruction. Univariate and multivariate logistic regression analyses were performed to compare the difference in KRAS mutation status between groups. RESULTS: In the LCC group, SAD, tumor shape, degree of pericolic fat stranding, and bowel obstruction were significant indicators for predicting KRAS status (P < 0.05). In the RCC group, CA19-9, SAD, and intratumoral low-density range were significant indicators for predicting KRAS status (P < 0.05.). The area under the curve (AUC) of the combination image indicators in the LCC group was 0.802 [cutoff point 0.372, 95% confidence interval (CI) 0.718-0.888, sensitivity 85.4%, specificity 72.0%]. The AUC in the RCC group was 0.828 (cutoff point 0.647, 95% CI 0.726-0.931, sensitivity 79.5%, specificity 75.0%). CONCLUSION: The CT imaging features associated with KRAS mutation status in the LCC and RCC groups were different. The combination of tumor location and imaging features can help to further improve the predictive value of KRAS status.

A Redox-Activatable DNA Nanodevice for Spatially-Selective, AND-Gated Imaging of ATP and Glutathione in Mitochondria.

Design of biosensors capable of imaging ATP and glutathione (GSH) in mitochondria remains a challenge, despite their importance in elucidating their correlated pathophysiological events. Here, we report a new strategy that uses redox-activatable aptamer sensor design combined with nanoparticle-based targeting capability to achieve spatially controlled, AND-gated imaging of ATP and GSH in mitochondria. The DNA nanodevice was designed by the controlled assembly of the redox-responsive ATP aptamer probe on the nanoparticles and further decorated with mitochondria-targeting signals. We demonstrate that the system allows for mitochondria-specific, correlated imaging of ATP and GSH in living cells and in vivo. Furthermore, because the system can be lighted up only when meeting the "dual keys" (overexpressed ATP and GSH in mitochondria) simultaneously, the DNA nanodevice enables specific imaging of tumors in vivo with improved tumor-to-normal tissue ratio. This work illustrates the potential of the DNA nanodevices in the imaging of mitochondrial multivariate targets.

Inhibition of MDA-MB-231 cell proliferation by pHLIP(Var7)-P1AP and SPECT imaging of MDA-MB-231 breast cancer-bearing nude mice using 125I-pHLIP(Var7)-P1AP.

AIM: To observe the effect of pHLIP(Var7)-P1AP on the proliferation of MDA-MB-231 triple-negative breast cancer cells and the small-animal single-photon-emission computed tomography (SPECT) imaging of breast cancer-bearing mice carrying MDA-MB-231 cells. METHODS: Peptide pHLIP(Var7)-P1AP was synthesized by solid-phase peptide synthesis. The binding of fluorescently labeled pHLIP(Var7)-P1AP to MDA-MB-231 cells under various pH conditions and its effect on MDA-MB-231 cell proliferation were analyzed. pHLIP(Var7)-P1AP was labeled with 125I, and the biological distribution of 125I-pHLIP(Var7)-P1AP in the breast cancer mouse model carrying MDA-MB-231 cells as well as the outcome of small-animal SPECT imaging were evaluated. RESULTS: pHLIP(Var7)-P1AP was successfully synthesized. Under pH 6.0, fluorescently labeled pHLIP(Var7)-P1AP had a higher binding ability to MDA-MB-231 cells and significantly inhibited the proliferation of MDA-MB-231 cells. The labeling efficiency of pHLIP(Var7)-P1AP with 125I was 33.1 ±â€Š2.7 %, and the radiochemical purity was 98.5 ±â€Š1.8 %. 125I-pHLIP(Var7)-P1AP showed a high concentration in tumors. Small-animal SPECT imaging showed clearly visible tumors at 4 h after injection. CONCLUSIONS: In the acidic environment, pHLIP(Var7)-P1AP can efficiently target MDA-MB-231 cells and inhibit their growth. Small-animal SPECT of 125I-pHLIP(Var7)-P1AP can clearly image tumors.

[Predicting pharmacokinetics of anti-cancer drug, famitinib in human using physiologically based pharmacokinetic model].

This study is to establish physiologically based pharmacokinetic (PBPK) models of famitinib in rat and monkey, and then to predict the pharmacokinetics and tissue distribution of famitinib in human based on the PBPK models. According to published paper, previous studies and the chemical properties of famitinib predicted by ACD/ADME suite and SimCYP, the PBPK models of rat and monkey were established and optimized using GastroPlus. And then, the PBPK models were applied to predict the pharmacokinetic and tissue distribution of famitinib in human. The results showed that the PBPK models of rat and monkey can fit the observed data well, and the AUC0-∞, ratios of observed and calculated data in rat and monkey were 1.00 and 0.97, respectively. The AUC0-∞, ratios of observed and predicted data in human were 1.63 (rat to human) and 1.57 (monkey to human), respectively. The rat and monkey PBPK models of famitinib were well established, and the PBPK models were applied in predicting pharmacokinetic of famitinib in human successfully. Hence, the PBPK model of famitinib in human could be applied in future drug-drug interaction study.

Radiolabeling LyP-1 peptide and preliminary biodistribution evaluation in mice bearing MDA-MB-435 xenografts.

BACKGROUND: Recent studies have shown the LyP-1 peptide can home to either tumor lymphatics or the tumor cells and be internalized by targeted cells. This study aimed to investigate the possibility of using Na(131)I labeled LyP-1 peptide as an imaging agent or a therapeutic radiopharmaceutical in breast carcinoma and its metastasis. METHODS: The 10-mer cyclic peptide contained the LyP-1 sequence (YCGNKRTRGC) was synthesized by the solid phase method. Disulfide bonds between the cysteines maintain the cyclic structure. The LyP-1 peptide was labeled with Na(131)I using the chloramine-T method. The [(131)I] LyP-1 peptide and a [(131)I] control peptide were injected via tail vein into nude mice bearing MDA-MB-435 tumor xenografts. Biodistribution and imaging results in vivo were obtained. RESULTS: The labeling efficiencies of LyP-1 peptide reached 80% ± 5% (n = 5). The radiochemical purity was about 96%. The radiochemical purity of the labeled compound remains 92% at 24 hours in human serum at 37°C. In the biodistribution studies, the [(131)I] LyP-1 peptide accumulated in the tumor to a higher level than in other organs. The [(131)I] LyP-1 peptide can successfully image the tumor in nude mice bearing MDA-MB-435 tumor xenografts. CONCLUSIONS: The LyP-1 peptide could be effectively labeled with Na(131)I and the labeled compound is stable in human serum at 37°C for 24 hours. The high specificity of [(131)I] LyP-1 peptide suggests it may be a promising new radiotracer for identifying tumors.

Use of Radioiodinated Peptide Arg-Arg-Leu Targeted to Neovasculari- zation as well as Tumor Cells in Molecular Tumor Imaging.

OBJECTIVE: To explore a tumor peptide imaging agent Arginine-Arginine-Leucine (Tyr-Cys-Gly-Gly-Arg-Arg- Leu-Gly-Gly-Cys, tripeptide RRL [tRRL]) that targeted to tumor cells and tumor-derived endothelial cells (TDECs) and primarily investigate the possible relationship between tRRL and vascular endothelial growth factor receptor 2 (VEGFR-2). METHODS: The tRRL sequence motif was identified as a tumor molecular marker specifically binding to TDECs. Tyrosine was conjugated to the amino terminal of RRL (Cys-Gly-Gly-Arg-Arg-Leu-Gly-Gly-Cys) for labeling with radionuclide iodine-131 ((131)I-tRRL). The uptake ability and molecular binding of tRRL to tumor cells and angiogenic endothelium were studied using flow cytometry and radioactivity counter in vitro. Whether VEGFR-2 is the binging site of tRRL was investigated. Biodistribution and single-photon emission computed tomography (SPECT) imaging of (131)I-tRRL were used to evaluate the effectiveness of this new imaging agent to visualize varied tumor xenografts in nude mice. RESULTS: In vitro cellular uptake experiments revealed that tRRL could not only adhere to tumor angiogenic endothelial cells but also largely accumulate in malignant tumor cells. VEGFR-2, which is highly expressed on TDECs, was probably not the solely binding ligand for tRRL targeted to tumor angiogenic endothelium. (131)I-tRRL mainly accumulated in tumors in vivo, not other organs at 24 h after injection. SPECT imaging with (131)I-tRRL clearly visualized tumors in nude mice, especially at 24 h. CONCLUSION: Radioiodinated tRRL offers a noninvasive nuclear imaging method for functional molecular imaging of tumors targeted to neovascularization, and may be a promising candidate for tumor radioimmunotherapeutic carrier.

Noninvasive visualization of RNA delivery with 99mTc-radiolabeled small-interference RNA in tumor xenografts.

UNLABELLED: Small-interference RNAs (siRNAs) are short, double-strand RNA molecules that target specific messenger RNAs for degradation via the process termed RNA interference. The efficacy of RNA interference depends greatly on effective delivery of siRNA, which calls for noninvasive methods for tracing siRNA in vivo. The purpose of this work was to develop a novel (99m)Tc-radiolabeled method to visualize siRNA targeting of a tumor biomarker of human telomerase reverse transcriptase (hTERT) in HepG2 tumor xenografts. METHODS: After conjugation with S-acetyl N-hydroxysuccinimide-mercaptoacetyltriglycine (NHS-MAG3), antisense RNA with 2'-O-methyl modification was annealed with sense strand to form a duplex and then radiolabeled with (99m)Tc. (99m)Tc-siRNAs were tested for stability in serum by measurement of radiochemical purity and for inhibitory activity by reverse-transcriptase polymerase chain reaction and Western blotting. In vitro cellular uptake was evaluated in HepG2 cells. Biodistribution studies and static imaging were performed in HepG2 tumor-bearing mice. RESULTS: Radiochemical purity remained highly stable in saline and fresh human serum at room temperature and 37 degrees C. Radiolabeled siRNA demonstrated strong inhibitory effects similar to those of unlabeled siRNA on both hTERT messenger RNA and protein in vitro. (99m)Tc-hTERT siRNA showed more uptake than did control siRNA in HepG2 cells after 1 h of incubation. After administration in HepG2 tumor-bearing mice, (99m)Tc-hTERT siRNA had significantly higher accumulation in tumors and a higher tumor-to-blood ratio than did control siRNA (P < 0.05). Scintigraphy of (99m)Tc-hTERT siRNA showed clear tumor images at 0.5, 1, 3, and 6 h after injection. In contrast, (99m)Tc-control siRNA failed to visualize the tumor. Ratios of uptake in tumor to uptake in contralateral region of hTERT-targeted siRNA were significantly higher than those of control siRNA (P < 0.05) at each time point. CONCLUSION: The (99m)Tc radiolabeling method with NHS-MAG3 chelator can be used successfully in siRNA radiolabeling, allowing for the noninvasive visualization of siRNA delivery in vivo.

[Uptake kinetics of hTERT antisense molecular probe by cells and its biological properities].

OBJECTIVE: To observe the cell uptake kinetics and specific gene expression effect of hTERT antisense molecular probe in vitro. METHODS: Antisense molecular probes targeting hTERT mRNA were radiolabeled with technetium-99m by the method of bifunctional chelator. HepG2 cells expressing hTERT were cultured. The uptake kinetics of molecular probes mediated by liposome or not in cells were examined in vitro. RT-PCR (reverse transcriptase polymerase chain reaction) method was performed to assay the specific gene expression effect of the molecular probes. All data were analyzed by the statistic software of SPSS 12.0. RESULTS: The labeling efficiencies of molecular probe reached (76 +/- 5) % (n = 5), the specific activity was up to 1.850 x 10(6) Bq/microg, and the radiochemical purity was above 96% after purification. The absolute accumulation of (99m)Tc, whether on antisense or sense molecular probe, was clearly higher with liposome-mediated than without liposome-mediated (P < 0.05). Furthermore, liposome advanced the peak time of cellular uptake of antisense molecular probe, with the highest accumulation occurring at the end of 2 h, and remaining at the same level till 3 h later. In comparison with sense molecular probe, antisense molecular probe preserved the capacity to bind living hTERT-expressing cells specifically and inhibited the expression of hTERT mRNA significantly as well as ASON. CONCLUSION: Liposome-mediated method could increase cell uptake of molecular probes in vitro. Antisense molecular probe preserved the capacity to inhibit the expression of targeting mRNA specifically. All results provided the basis for further in vivo study.

{6,6'-Dimeth-oxy-2,2'-[4-bromo-o-phenyl-enebis(nitrilo-methyl-idyne)]diphenolato}nickel(II) methanol solvate.

In the title compound, [Ni(C(22)H(17)BrN(2)O(4))]·CH(3)OH, the Ni(II) ion is in a slightly distorted square-planar geometry involving an N(2)O(2) atom set of the tetra-dentate Schiff base ligand. The asymmetric unit contains one nickel complex and one methanol solvent mol-ecule. The dihedral angle between the aromatic ring planes of the central aromatic ring and other two aromatic rings are 10.8 (3) and 6.0 (2)°. The crystal structure is stabilized by inter-molecular C-H⋯O and C-H⋯Br and by intra-molecular O-H⋯O hydrogen bonds.

Tris(1,10-phenanthroline-κN,N')iron(II) µ-oxido-bis[trichloridoferrate(III)] ethanol hemisolvate.

The title compound, [Fe(C(12)H(8)N(2))(3)][Fe(2)Cl(6)O]·0.5CH(3)CH(2)OH, consists of one [Fe(phen)(3)](2+) cation (phen = 1,10-phen-anthroline), one [Fe(2)Cl(6)O](2-) anion and one half-mol-ecule of ethanol. In the cation, the Fe(II) atom is coordinated by six N atoms from three phen ligands in a distorted octa-hedral geometry. In the bent anion, two Fe(III) atoms are connected by a bridging oxide O atom [bridging angle = 160.6 (4)°], and each Fe(III) atom is also coordinated by three Cl atoms, completing a distorted tetra-hedral geometry.

Noninvasive imaging of human telomerase reverse transcriptase (hTERT) messenger RNA with 99mTc-radiolabeled antisense probes in malignant tumors.

UNLABELLED: The expression of human telomerase reverse transcriptase (hTERT) is present in most malignant cells (>85%) but is undetectable in most normal somatic cells. Visualization of hTERT expression using radionuclide targeting can provide important diagnostic information in malignant tumors. The overall aim of this study was to evaluate whether (99m)Tc-radiolabeled antisense oligonucleotide (ASON) targeting hTERT messenger RNA (mRNA) can be used for imaging of hTERT expression in vivo. METHODS: One 18-mer antisense or sense uniformly phosphorothioate-modified oligonucleotide targeting hTERT mRNA was radiolabeled with (99m)Tc through the bifunctional chelator N-hydroxysuccinimidyl derivative of S-acetylmercaptoacetyltriglycine (S-acetyl NHS-MAG3). Then the radiolabeled probe was characterized in vitro. Reverse transcription-polymerase chain reaction (RT-PCR) was performed to assay the mRNA level after proliferating cells had been incubated with the antisense and sense probes. (99m)Tc-MAG3-ASON or (99m)Tc-MAG3-SON was injected intravenously in mammary tumor-bearing BALB/c nude mice. Biodistribution and in vivo imaging was performed periodically. All data were analyzed by statistical software. RESULTS: The labeling efficiencies of (99m)Tc-MAG3-ASON/SON reached 76% +/- 5% (n = 5) within 15-30 min at room temperature, the specific activity was up to 1,850 kBq/mug, and the radiochemical purity was >96% after purification. (99m)Tc-MAG3-ASON showed complete stability at room temperature and in fresh 37 degrees C human serum. In comparison with (99m)Tc-MAG3-SON, (99m)Tc-MAG3-ASON preserved the capacity to bind living hTERT-expressing cells specifically and to inhibit the expression of hTERT mRNA significantly as well as ASON. In nude mice bearing hTERT-expressing MCF-7 xenografts, tumor radioactivity uptake of (99m)Tc-MAG3-ASON after injection was significantly higher than that of (99m)Tc-MAG3-SON after injection (P < 0.05). The hTERT-expressing xenografts were clearly imaged at 4-8 h noninvasively after injection of (99m)Tc-MAG3-ASON, whereas the xenografts were not imaged at any time after injection of (99m)Tc-MAG3-SON. CONCLUSION: This in vivo study provides evidence that (99m)Tc-MAG3-ASON targeting hTERT mRNA can be used as a potential candidate for visualization of hTERT expression in carcinomas.