Diagnostic Performance of Surgical Indication for Branch-duct or Mixed-type Intraductal Papillary Mucinous Neoplasms of the Revised International Association of Pancreatology (IAP) 2023 Guidelines.

OBJECTIVE: To evaluate the diagnostic performance of surgical indications of the revised International Association of Pancreatology (IAP) 2023 guidelines compared to the IAP 2017 and European 2018 guidelines. SUMMARY BACKGROUND DATA: The revised IAP guidelines for surgical indications for branch duct (BD) intraductal papillary mucinous neoplasms (IPMN) include the presence of at least two worrisome features without mandatory endoscopic ultrasound. METHODS: Among 663 patients who underwent resection for pathologically confirmed IPMN in a tertiary hospital between 2013 and 2023, 556 patients with BD or mixed-type IPMN were retrospectively reviewed. Diagnostic performances of the three guidelines for predicting high-grade dysplasia or IPMN with invasive carcinoma were compared. The primary outcome was the malignancy rate. Clinicopathological and radiological imaging data were analyzed. RESULTS: A total of 540, 451, and 490 patients met the surgical indications of the IAP, 2017, 2023, and European guidelines, respectively. Malignant IPMN was observed in 229 (41.2%) patients (high-grade dysplasia, n=99; invasive carcinoma, n=130). Surgical indication by the IAP 2023 guidelines showed higher specificity (29.1 vs. 4.9%, P<0.001), positive predictive value (48.6 vs. 42.4%, P=0.031), and accuracy (55.5 vs. 44.1%, P<0.001) than the IAP 2017 guidelines. It also had higher specificity than the European guidelines (18.7%, P=0.024). The IAP 2023 guidelines showed a superior AUC of surgical indication (0.623 vs. 0.582 for the European guidelines, P<0.001; and 0.524 for the IAP guidelines, P=0.008). CONCLUSIONS: The IAP 2023 guidelines showed better malignancy prediction than the IAP 2017 and European guidelines, potentially reducing unnecessary surgeries.

Clinical outcomes of preservation versus resection of portal/superior mesenteric vein during pancreaticoduodenectomy in pancreatic cancer patients who respond to neoadjuvant treatment: A retrospective cohort study.

BACKGROUND: R0 rates have increased as neoadjuvant treatment (NAT) has become the primary treatment for pancreatic ductal adenocarcinoma (PDAC) with venous involvement, suggesting a decrease in venous tumor infiltration. The aim of this study was to investigate the clinical outcomes of preserving the portal/superior mesenteric vein (PV/SMV) during pancreaticoduodenectomy (PD) in PDAC patients who underwent NAT. MATERIAL AND METHODS: The 113 patients with resectable and borderline resectable PDAC with venous involvement who responded to NAT and underwent curative PD between 2012 and 2022 were retrospectively reviewed. RESULTS: Among the 113 patients, PV/SMV preservation (PVP) was performed in 68 patients (60.2%), and PV/SMV resection (PVR) was performed in 45 patients (39.8%). There was no significant difference in the R0 rate, 5-year overall survival (OS) and recurrence-free survival between the two groups. PV/SMV stenosis within 3 months after surgery was more common in the PVR group than in the PVP group (1.5% versus 22.2%; P < 0.001), and 5-year PV/SMV stenosis-free survival was significantly higher in the PVP group than in the PVR group (76.5% versus 53.4%; P=0.014). Multivariate analysis showed that gemcitabine-based neoadjuvant chemotherapy was associated with poor OS. PVR, clinically relevant postoperative pancreatic fistula, and locoregional recurrence were independent risk factors for PV/SMV stenosis. CONCLUSION: The PVP group had similar oncologic outcomes and better vessel-functional outcomes than the PVR group. Therefore, if dissection is possible and there is a high likelihood of achieving R0 resection after NAT, routine PVR may be unnecessary in PDAC patients with venous involvement.

Comparing clinical and genomic features based on the tumor location in patients with resected pancreatic cancer.

BACKGROUND: Pancreatic cancer is anatomically divided into pancreatic head and body/tail cancers, and some studies have reported differences in prognosis. However, whether this discrepancy is induced from the difference of tumor biology is hotly debated. Therefore, we aimed to evaluate the differences in clinical outcomes and tumor biology depending on the tumor location. METHODS: In this retrospective cohort study, we identified 800 patients with pancreatic ductal adenocarcinoma who had undergone upfront curative-intent surgery. Cox regression analysis was performed to explore the prognostic impact of the tumor location. Among them, 153 patients with sufficient tumor tissue and blood samples who provided informed consent for next-generation sequencing were selected as the cohort for genomic analysis. RESULTS: Out of the 800 patients, 500 (62.5%) had pancreatic head cancer, and 300 (37.5%) had body/tail cancer. Tumor location in the body/tail of the pancreas was not identified as a significant predictor of survival outcomes compared to that in the head in multivariate analysis (hazard ratio, 0.94; 95% confidence interval, 0.77-1.14; P = 0.511). Additionally, in the genomic analyses of 153 patients, there were no significant differences in mutational landscapes, distribution of subtypes based on transcriptomic profiling, and estimated infiltration levels of various immune cells between pancreatic head and body/tail cancers. CONCLUSIONS: We could not find differences in prognosis and tumor biology depending on tumor location in pancreatic ductal adenocarcinoma. Discrepancies in prognosis may represent a combination of lead time, selection bias, and clinical differences, including the surgical burden between tumor sites.

Interactions of bosutinib with drug transporters: In vitro and In vivo inhibition of organic cation transporter 2, multidrug and toxin extrusion protein 1, and breast cancer resistance protein by bosutinib.

Bosutinib has been approved for use in patients with chronic myeloid leukemia. Information regarding the effects of bosutinib on clinically important drug transporters is limited, particularly regarding its inhibitory potency on transporters and in vivo effects. Therefore, we conducted a study investigating the in vitro and in vivo effects of bosutinib on drug transporters. Bosutinib showed moderate or strong inhibitory effects on organic cation transporter 2, multidrug and toxin extrusion protein 1, and breast cancer resistance protein with IC50 values of 0.0894, 0.598, and 10.8 µM, respectively. In vivo experiments in rats showed that bosutinib significantly inhibited organic cation transporter 2 and multidrug and toxin extrusion protein 1, leading to a marked reduction in the renal clearance of metformin and an increase in systemic exposure to metformin. Bosutinib increased systemic exposure to sulfasalazine, a probe substrate of breast cancer resistance protein, by 75 % in rats, highlighting its potential to significantly affect intestinal drug efflux. These quantitative changes suggest that bosutinib may alter the in vivo pharmacokinetics of drugs that are substrates of these transporters, potentially leading to increased drug exposure and enhanced or unexpected pharmacological effects.

Re-evaluation of risk and oncological outcomes of resection of veins and arteries in the resection of pancreatic cancer.

BACKGROUND: Advances in chemotherapy have led to increasing major vascular resection during pancreatectomy which has been contraindicated due to high morbidity. This study aimed to verify the safety and oncological outcomes of vascular resection during pancreatectomy in the era of neoadjuvant therapy. METHODS: Data from patients who underwent surgery for pancreatic cancer at Seoul National University Hospital between 2001 and 2021 were reviewed. Clinicopathological outcomes were analyzed according vessel resection. A propensity-score-matched (PSM) analysis was performed to evaluate survival outcomes. RESULTS: Of 1596 patients, the proportion of those who underwent vascular resection increased from 9.2% to 23.4% over time divided into 5-year intervals. There were no differences in major complications (15.6% vs. 13.0%; p = .266) and 30-day mortality rate (0.3% vs. 0.6%; p = .837) between the vascular and nonvascular resection groups. After PSM, the vascular resection group demonstrated comparable survival outcome with the nonvascular resection group (5 year-survival-rate 20.4 vs. 23.7%; p = .194). Arterial resection yielded comparable survival outcome with nonvascular resection (5 year-survival-rate 38.1% vs. 23.7%; p = .138). CONCLUSIONS: Appropriate vascular resection-even arterial-is safe and effective in patients carefully selected for radical surgery in the era of neoadjuvant therapy. Further studies are needed to determine the optimal indication and method for vascular resection in patients with pancreatic cancer.

Roles of breast cancer resistance protein and organic anion transporting polypeptide 2B1 in gastrointestinal toxicity induced by SN-38 under inflammatory conditions.

Drug transporters are among the factors that determine the pharmacokinetic profiles after drug administration. In this study, we investigated the roles of drug transporters involved in transport of SN-38, which is an active metabolite of irinotecan, in the intestine under inflammatory conditions in vitro and determined their functional consequences. The expression alterations of breast cancer resistance protein (BCRP) and organic anion transporting polypeptide (OATP) 2B1 were determined at the mRNA and protein levels, and the subsequent functional alterations were evaluated via an accumulation study with the representative transporter substrates [prazosin and dibromofluorescein (DBF)] and SN-38. We also determined the cytotoxicity of SN-38 under inflammatory conditions. Decreased BCRP expression and increased OATP2B1 expression were observed under inflammatory conditions in vitro, which led to altered accumulation profiles of prazosin, DBF, and SN-38, and the subsequent cytotoxic profiles of SN-38. Treatment with rifampin or novobiocin supported the significant roles of BCRP and OATP2B1 in the transport and cytotoxic profile of SN-38. Collectively, these results suggest that BCRP and OATP2B1 are involved in the increased cytotoxicity of SN-38 under inflammatory conditions in vitro. Further comprehensive research is warranted to completely understand SN-38-induced gastrointestinal cytotoxicity and aid in the successful treatment of cancer with irinotecan.

Long-Term Outcome of Proximal Gastrectomy for Upper-Third Advanced Gastric and Siewert Type II Esophagogastric Junction Cancer Compared With Total Gastrectomy: A Propensity Score-Matched Analysis.

BACKGROUND: This study aimed to investigate the oncologic long-term safety of proximal gastrectomy for upper-third advanced gastric cancer (AGC) and Siewert type II esophagogastric junction (EGJ) cancer. METHODS: The study enrolled patients who underwent proximal gastrectomy (PG) or total gastrectomy (TG) with standard lymph node (LN) dissection for pathologically proven upper-third AGC and EGJ cancers between January 2007 and December 2018. Propensity score-matching with a 1:1 ratio was performed to reduce the influence of confounding variables such as age, sex, tumor size, T stage, N stage, and tumor-node-metastasis (TNM) stage. Kaplan-Meier survival analysis was performed to analyze oncologic outcome. The prognostic factors of recurrence-free survival (RFS) were analyzed using the Cox proportional hazard analysis. RESULTS: Of the 713 enrolled patients in this study, 60 received PG and 653 received TG. Propensity score-matching yielded 60 patients for each group. The overall survival rates were 61.7 % in the PG group and 68.3 % in the TG group (p = 0.676). The RFS was 86.7 % in the PG group and 83.3 % in the TG group (p = 0.634). The PG group showed eight recurrences (1 anastomosis site, 1 paraaortic LN, 1 liver, 1 spleen, 1 lung, 1 splenic hilar LN, and 2 remnant stomachs). In the multivariate analysis, the operation method was not identified as a prognostic factor of tumor recurrence. CONCLUSION: The patients who underwent PG had a long-term oncologic outcome similar to that for the patients who underwent TG for upper-third AGC and EGJ cancer.

Pharmacokinetic interactions of niclosamide in rats: Involvement of organic anion transporters 1 and 3 and organic cation transporter 2.

Niclosamide is an anthelmintic drug with a long history of use and is generally safe and well tolerated in humans. As the conventional dose of niclosamide results in a low but certain level in systemic circulation, drug interactions with concomitant drugs should be considered. We aimed to investigate the interaction between niclosamide and drug transporters, as such information is currently limited. Niclosamide inhibited the transport activity of OATP1B1, OATP1B3, OAT1, OAT3, and OCT2 in vitro. Among them, the inhibitory effects on OAT1, OAT3, and OCT2 were strong, with IC50 values of less than 1 µM. When 3 mg/kg of niclosamide was co-administered to rats, systemic exposure to furosemide (a substrate of OAT1/3) and metformin (a substrate of OCT2) increased, and the renal clearance (CLr) of the drugs significantly decreased. These results suggest that niclosamide inhibits renal transporters, OAT1/3 and OCT2, not only in vitro but also in vivo, resulting in increased systemic exposure to the substrates of the transporters by strongly blocking the urinary elimination pathway in rats. The findings of this study will support a meticulous understanding of the transporter-mediated drug interactions of niclosamide and consequently aid in effective and safe use of niclosamide.

Optimal Surveillance Interval of Branch Duct Intraductal Papillary Mucinous Neoplasm of the Pancreas.

Importance: Despite the increasing prevalence of intraductal papillary mucinous neoplasm (IPMN), data on the growth and malignant conversion rates based on long-term surveillance cohorts are limited. Many international guidelines recommend surveillance for benign lesions, but the optimal interval and duration are unclear. Objective: To determine the optimal surveillance protocol for IPMN and propose which patients may be exempted from surveillance. Design, Setting, and Participants: This large-scale, international cohort study examined data of 3825 patients with IPMN treated at 5 tertiary pancreatic centers. Included were patients with branch duct (BD) IPMN who underwent surveillance or surgery between January 1, 1988, and December 31, 2020. After a thorough review, 3656 patients were included in the analytic sample. Changes in cyst size, worrisome features or high-risk stigmata, and malignant conversion rates were assessed. Patients who underwent surveillance over 5 years were compared to suggest discontinuation of surveillance protocol. Clinical data collection began in January 1, 2021, and the mean (SD) follow-up duration was 84 (47.7) months. The data analysis was performed from May 2, 2022, through September 14, 2022. Exposure: The patients with BD-IPMN were followed up based on International Association of Pancreatology guidelines. Patients with suspicious malignant neoplasms during surveillance underwent surgical resection. Main Outcome and Measures: The main outcome of this study was the optimal follow-up interval and duration of BD-IPMN surveillance. The association among cyst size, growth rate, and progression was examined using descriptive statistics. Results: Of the 3656 patients with BD-IPMN in the analytic sample (1973 [54.0%] female; mean [SD] age, 63.7 [10.2] years), 172 (4.7%) were confirmed to have malignant lesions through surgery. Considering cyst growth, the time to develop worrisome features, and malignant conversion, a 1.5-, 1-, and 0.5-year surveillance interval could be optimal for cysts smaller than 20 mm, 20 to 30 mm, and 30 mm, respectively, after initial short-term (6-month) follow-up. Patients with cysts smaller than 20 mm, no worrisome features, and no growth during 5-year surveillance did not show malignant conversion after 5 years of follow-up and had time to progression of greater than 10 years. Conclusions: These findings suggest that BD-IPMN surveillance may depend on the size of the cyst and morphologic changes at the initial 6-month follow-up. For patients with small cysts (ie, <20 mm) with no morphologic changes during the initial 5-year surveillance period, surveillance may be discontinued for those unfit for surgery or who have a limited life expectancy of 10 years or less.

The Multidomain Metaverse Cancer Care Digital Platform: Development and Usability Study.

BACKGROUND: As cancer treatment methods have diversified and the importance of self-management, which lowers the dependence rate on direct hospital visits, has increased, effective cancer care education and management for health professionals and patients have become necessary. The metaverse is in the spotlight as a means of digital health that allows users to engage in cancer care education and management beyond physical constraints. However, it is difficult to find a multipurpose medical metaverse that can not only be used in the field but also complements current cancer care. OBJECTIVE: This study aimed to develop an integrated metaverse cancer care platform, Dr. Meta, and examine its usability. METHODS: We conducted a multicenter, cross-sectional survey between November and December 2021. A descriptive analysis was performed to examine users' experiences with Dr. Meta. In addition, a supplementary open-ended question was used to ask users for their suggestions and improvements regarding the platform. RESULTS: Responses from 70 Korean participants (male: n=19, 27% and female: n=51, 73%) were analyzed. More than half (n=37, 54%) of the participants were satisfied with Dr. Meta; they responded that it was an interesting and immersive platform (n=50, 72%). Less than half perceived no discomfort when using Dr. Meta (n=34, 49%) and no difficulty in wearing and operating the device (n=30, 43%). Furthermore, more than half (n=50, 72%) of the participants reported that Dr. Meta would help provide non-face-to-face and noncontact services. More than half also wanted to continue using this platform in the future (n=41, 59%) and recommended it to others (n=42, 60%). CONCLUSIONS: We developed a multidomain metaverse cancer care platform that can support both health professionals and patients in non-face-to-face cancer care. The platform was uniquely disseminated and implemented in multiple regional hospitals and showed the potential to perform successful cancer care.

Characteristics of Human Nasal Turbinate Stem Cells under Hypoxic Conditions.

This study investigated the influence of hypoxic culture conditions on human nasal inferior turbinate-derived stem cells (hNTSCs), a subtype of mesenchymal stem cells (MSCs). It aimed to discern how hypoxia affected hNTSC characteristics, proliferation, and differentiation potential compared to hNTSCs cultured under normal oxygen levels. After obtaining hNTSCs from five patients, the samples were divided into hypoxic and normoxic groups. The investigation utilized fluorescence-activated cell sorting (FACS) for surface marker analysis, cell counting kit-8 assays for proliferation assessment, and multiplex immunoassays for cytokine secretion study. Differentiation potential-osteogenic, chondrogenic, and adipogenic-was evaluated via histological examination and gene expression analysis. Results indicated that hNTSCs under hypoxic conditions preserved their characteristic MSC phenotype, as confirmed by FACS analysis demonstrating the absence of hematopoietic markers and presence of MSC markers. Proliferation of hNTSCs remained unaffected by hypoxia. Cytokine expression showed similarity between hypoxic and normoxic groups throughout cultivation. Nevertheless, hypoxic conditions reduced the osteogenic and promoted adipogenic differentiation potential, while chondrogenic differentiation was relatively unchanged. These insights contribute to understanding hNTSC behavior in hypoxic environments, advancing the development of protocols for stem cell therapies and tissue engineering.

Strong inhibition of organic cation transporter 2 by flavonoids and attenuation effects on cisplatin-induced cytotoxicity.

Organic cation transporter 2 (OCT2) is predominantly expressed in the basolateral membrane of renal proximal tubule cells and contributes to the renal excretion of various drugs such as metformin, cisplatin, oxaliplatin, cimetidine, and lamivudine. Cisplatin, an anticancer agent for various cancers, is a substrate of OCT2, and cisplatin-induced nephrotoxicity is in part attributed to OCT2 activity in the kidney, which increases the renal accumulation of cisplatin. In this study, we aimed to identify flavone derivatives with strong inhibitory effects on OCT2 transport. Among the 80 flavonoids tested, 24 showed moderate to strong inhibitory effects against OCT2 transport activity. The IC50 values were less than 5 µM for 10 flavonoids. All 10 compounds alleviated cisplatin-induced cytotoxicity in cells expressing OCT2, even though the magnitude of the effects varied depending on the functional moieties in each position. Multiple factor analysis revealed that the methyl group at the R1 position and methoxy group at the R6 position of the flavonol backbone are important for OCT2 inhibition. Information on the functional moieties in the flavonol backbone would help develop effective OCT2 inhibitors by providing a structural association with OCT2 inhibitory effects. In addition, the compounds with strong inhibitory effects on OCT2 identified in this study may be potential candidates for clinical use to mitigate cisplatin-induced nephrotoxicity.

The In Vitro and In Vivo Anticancer Effect of Photomed for Photodynamic Therapy: Comparison with Photofrin and Radachlorin.

To overcome the limitation of conventional cancer treatments, photodynamic therapy (PDT) has been introduced as another treatment option. PDT provides a non-invasive, non-surgical way with reduced toxicity. To improve the antitumor efficacy of PDT, we synthesized a novel photosensitizer, a 3-substituted methyl pyropheophorbide-a derivative (Photomed). The purpose of the study was to evaluate the antitumor effect of PDT with Photomed comparing with the clinically approved photosensitizers Photofrin and Radachlorin. The cytotoxicity assay against SCC VII cells (murine squamous cell carcinoma) was performed to determine whether Photomed is safe without PDT and whether Photomed is effective against cancer cells with PDT. An in vivo anticancer efficacy study was also performed using SCC VII tumor-bearing mice. The mice were divided into small-tumor and large-tumor groups to identify whether Photomed-induced PDT is effective for not only small tumors but also large tumors. From in vitro and in vivo studies, Photomed was confirmed to be (1) a safe photosensitizer without laser irradiation, (2) the most effective photosensitizer with PDT against cancers compared to Photofrin and Radachlorin and (3) effective with PDT in treating not only small tumors but also large tumors. In conclusion, Photomed may contribute as a novel, potential photosensitizer for use in PDT cancer treatment.

Role of the efflux transporters Abcb1 and Abcg2 in the brain distribution of olaparib in mice.

Olaparib is a first-in-class poly (ADP-ribose) polymerase oral inhibitor used to treat various tumors. In this study, we clarified the roles of ABCB1/Abcb1 and ABCG2/Abcg2 transporters in restricting olaparib distribution to the brain. Olaparib was efficiently transported by human ABCG2, human ABCB1, and mouse Abcg2 in vitro. In the in vivo disposition study of olaparib using single or combination knockout mice, the systemic exposure of olaparib did not differ significantly between the strains over an 8-h period. However, the brain-to-plasma unbound concentration ratio of olaparib increased 5.6- and 8.1-fold in Abcb1a/1b and Abcb1a/1b;Abcg2 knockout mice, respectively, compared with wild-type mice. The Abcg2 single knockout mice exhibited a similar brain-to-plasma unbound concentration ratio to wild-type mice. Moreover, the brain distribution of olaparib could be modulated by the ABCB1/ABCG2 dual inhibitor elacridar to reach a similar degree of inhibition to Abcb1a/1b-/-. These findings suggest that olaparib is actively transported by both human and mouse ABCB1/Abcb1 and ABCG2/Abcg2; while Abcb1a/1b is a major determinant of olaparib brain penetration in mice, Abcg2 is likely to be a minor contributor. Concomitant treatment with temozolomide slightly increased the brain distribution of olaparib in mouse, but the clinical impact of the interaction was expected to be limited.

CD40 Agonists Alter the Pancreatic Cancer Microenvironment by Shifting the Macrophage Phenotype toward M1 and Suppress Human Pancreatic Cancer in Organotypic Slice Cultures.

Background/Aims: CD40 agonists are thought to generate antitumor effects on pancreatic cancer via macrophages and T cells. We aimed to investigate the role of CD40 agonists in the differentiation of macrophages and treatment of human pancreatic adenocarcinoma. Methods: Immunohistochemistry was performed on paraffin-embedded surgical blocks from patients with pancreatic cancers to evaluate macrophage phenotypes and their relationship with survival. The effects of CD40 agonists on macrophage phenotypes and human pancreatic cancer were evaluated utilizing cell cocultures and organotypic slice cultures. Results: CD163+ (predominant in M2 macrophages) and FOXP3+ (predominant in regulatory T cells) expression levels in the tumors were significantly lower in patients with stage IB pancreatic cancer than in those with stage II or III disease (p=0.002 and p=0.003, respectively). Patients with high CD163+ expression had shorter overall survival than those with low CD163+ expression (p=0.002). In vitro treatment of THP-1 macrophages with a CD40 agonist led to an increase in HLA-DR+ (predominant in M1 macrophages) and a decrease in CD163+ expression in THP-1 cells. Cell cocultures showed that CD40 agonists facilitate the suppression of PANC-1 human pancreatic cancer cells by THP-1 macrophages. Organotypic slice cultures showed that CD40 agonists alter the pancreatic cancer microenvironment by shifting the macrophage phenotype toward M1 (increase HLA-DR+ and decrease CD163+ expression), decreasing the abundance of regulatory T cells, and increasing tumor cell apoptosis. Conclusions: CD163 is related to advanced human pancreatic cancer stages and shorter overall survival. CD40 agonists alter macrophage phenotype polarization to favor the M1 phenotype and suppress human pancreatic cancer.

Potential Therapeutic Approaches through Modulating the Autophagy Process for Skin Barrier Dysfunction.

Autophagy is an attractive process to researchers who are seeking novel potential treatments for various diseases. Autophagy plays a critical role in degrading damaged cellular organelles, supporting normal cell development, and maintaining cellular homeostasis. Because of the various effects of autophagy, recent human genome research has focused on evaluating the relationship between autophagy and a wide variety of diseases, such as autoimmune diseases, cancers, and inflammatory diseases. The skin is the largest organ in the body and provides the first line of defense against environmental hazards, including UV damage, chemical toxins, injuries, oxidative stress, and microorganisms. Autophagy takes part in endogenous defense mechanisms by controlling skin homeostasis. In this manner, regulating autophagy might contribute to the treatment of skin barrier dysfunctions. Various studies are ongoing to elucidate the association between autophagy and skin-related diseases in order to find potential therapeutic approaches. However, little evidence has been gathered about the relationship between autophagy and the skin. In this review, we highlight the previous findings of autophagy and skin barrier disorders and suggest potential therapeutic strategies. The recent research regarding autophagy in acne and skin aging is also discussed.

Pharmacokinetic Characterization of Supinoxin and Its Physiologically Based Pharmacokinetic Modeling in Rats.

Supinoxin is a novel anticancer drug candidate targeting the Y593 phospho-p68 RNA helicase, by exhibiting antiproliferative activity and/or suppression of tumor growth. This study aimed to characterize the in vitro and in vivo pharmacokinetics of supinoxin and attempt physiologically based pharmacokinetic (PBPK) modeling in rats. Supinoxin has good permeability, comparable to that of metoprolol (high permeability compound) in Caco-2 cells, with negligible net absorptive or secretory transport observed. After an intravenous injection at a dose range of 0.5-5 mg/kg, the terminal half-life (i.e., 2.54-2.80 h), systemic clearance (i.e., 691-865 mL/h/kg), and steady state volume of distribution (i.e., 2040-3500 mL/kg) of supinoxin remained unchanged, suggesting dose-independent (i.e., dose-proportional) pharmacokinetics for the dose ranges studied. After oral administration, supinoxin showed modest absorption with an absolute oral bioavailability of 56.9-57.4%. The fecal recovery following intravenous and oral administration was 16.5% and 46.8%, respectively, whereas the urinary recoveries in both administration routes were negligible. Supinoxin was mainly eliminated via NADPH-dependent phase I metabolism (i.e., 58.5% of total clearance), while UDPGA-dependent phase II metabolism appeared negligible in the rat liver microsome. Supinoxin was most abundantly distributed in the adipose tissue, gut, and liver among the nine major tissues studied (i.e., the brain, liver, kidneys, heart, lungs, spleen, gut, muscles, and adipose tissue), and the tissue exposure profiles of supinoxin were well predicted with physiologically based pharmacokinetics.

Saccharoquinoline, a Cytotoxic Alkaloidal Meroterpenoid from Marine-Derived Bacterium Saccharomonospora sp.

A cytotoxic alkaloidal meroterpenoid, saccharoquinoline (1), has been isolated from the fermentation broth of the marine-derived bacterium Saccharomonospora sp. CNQ-490. The planar structure of 1 was elucidated by 1D, 2D NMR, and MS spectroscopic data analyzes, while the relative configuration of 1 was defined through the interpretation of NOE spectroscopic data. Saccharoquinoline (1) is composed of a drimane-type sesquiterpene unit in combination with an apparent 6,7,8-trihydroxyquinoline-2-carboxylic acid. This combination of biosynthetic pathways was observed for the first time in natural microbial products. Saccharoquinoline (1) was found to have cytotoxicity against the HCT-116 cancer cell line by inducing G1 arrest, which leads to cell growth inhibition.

Organotypic slice cultures of pancreatic ductal adenocarcinoma preserve the tumor microenvironment and provide a platform for drug response.

BACKGROUND: /Objective: The conventional models currently used to evaluate various anti-tumor therapeutic agents are not sufficient for representing human pancreatic ductal adenocarcinoma (PDA), which has a unique tumor microenvironment. We aimed to produce an organotypic slice culture model from human PDA that resembles the in vivo situation and to evaluate the responses of PDA slices to established cytotoxic drugs. METHODS: PDA tissues were obtained from 10 patients who underwent pancreatic resection. The tissues were sliced by a vibratome, and the tumor slices were then cultured. The viability of tumor slices during slice culture was evaluated using H&E and immunohistochemical staining, and stromal cells were demonstrated. The effects of cytotoxic drugs on PDA cell lines and slices were analyzed. RESULTS: Tumor slices maintained their surface areas and tissue viability for at least five days during culture. Preserved proliferation and apoptosis in tumor slices were observed by the expression of Ki-67 and cleaved caspase-3. Stromal cells including macrophages (CD68+ and CD163+), T cells (CD3+, CD8+, and FOXP3+), and myeloid cells (CD11b+) were present throughout the culture period. Staurosporine, gemcitabine, and cisplatin treatment of PDA cell lines and tumor slices exerted proportional cytotoxic effects in terms of MTT viability, tumor cell number, and Ki-67 and cleaved caspase-3 expression. CONCLUSIONS: Organotypic human PDA slice cultures preserved their viability and tumor microenvironment for at least five days during slice culture. PDA slice culture appears to be a feasible preclinical test model to assess the response to anti-tumor agents.

Lodopyridones B and C from a marine sediment-derived bacterium Saccharomonospora sp.

HPLC-UV guided isolation of the culture broth of a marine bacterium Saccharomonospora sp. CNQ-490 has led to the isolation of two new natural products, lodopyridones B and C (1 and 2) along with the previously reported lodopyridone A (3). Their chemical structures were established from the interpretation of 2D NMR spectroscopic data and the comparison of NMR data with the lodopyridone A (3). Lodopyridones B and C (1 and 2) possess the thiazole, and chloroquinoline groups which are characteristic features of these molecules. Lodopyridones A-C show weak inhibitory activities on the ß-site amyloid precursor protein cleaving enzyme 1 (BACE1).