Catechol-O-methyltransferase and monoamine oxidase B inhibitory activities of Australian bee pollen.

Bee pollen is an apicultural product collected by honeybees from flower stamens and used as a functional food worldwide. In the present study, we aim to elucidate the functions of Australian bee pollen. Australian bee pollen extracts and their main components were tested for catechol-O-methyltransferase (COMT) and monoamine oxidase B (MAOB) inhibitory activities. These enzymes are key neurotransmitters involved in Parkinson's disease and depression. Myricetin (5), tricetin (6), and luteolin (7) exhibited high COMT inhibitory activities (half maximal inhibitory concentration [IC50] = 23.3, 13.8, and 47.4 µM, respectively). In contrast, 5, 7, and annulatin (8) exhibited MAOB inhibitory activities (IC50 = 89.7, 32.8, and 153 µM, respectively). Quantitative analysis via high-performance liquid chromatography revealed that 5 was abundant in Australian bee pollen extracts. Our findings suggest that 5 contributes to the COMT and MAOB inhibitory activities of Australian bee pollen.

Effect of a web-based fertility preservation training program for medical professionals in Japan.

BACKGROUND: Our web-based training program called "Educating Medical Professionals about Reproductive Issues in Cancer Healthcare" aims to help healthcare professionals communicate promptly with patients and survivors who are adolescents and young adults, with information pertinent to reproductive health issues such as the risk of infertility and fertility preservation. METHODS: The study participants were professional healthcare providers, including physicians, nurses, pharmacists, social workers, midwives, psychologists, laboratory technicians, genetic counselors, and dieticians. Pre- and post- and 3-month follow-up tests consisting of 41 questions were administered to measure changes in knowledge and confidence. The participants also received a follow-up survey that covered confidence, communication techniques, and practice habits. A total of 820 healthcare providers participated in this program. RESULTS: The mean total score from the pre-test to the post-test grew significantly (p < 0.01), and participants' self-confidence increased. In addition, there was a change in the behavior of healthcare providers, who began asking about patients' marital status and parity. CONCLUSION: Our web-based fertility preservation training program improved knowledge and self-confidence regarding fertility preservation issues among healthcare providers caring for adolescents and young adult cancer patients and survivors.

Risk-reducing mastectomy for women with hereditary breast and ovarian cancer (HBOC): analytical results of data from the Japanese Organization of HBOC.

BACKGROUND: Risk-reducing mastectomy is one option for women with hereditary breast and ovarian cancer to reduce the risk of breast cancer. PATIENTS AND METHODS: We analyzed data of the Japanese Organization of Hereditary Breast and Ovarian Cancer on women who were diagnosed as hereditary breast and ovarian cancer by BRCA germline genetic testing between 2010 and 2019 to reveal the rate and likelihood of risk-reducing mastectomy. RESULTS: There were 412 women with BRCA1, 271 with BRCA2 and 4 with both female pathogenic variants. Ninety (13.1%) received risk-reducing mastectomy. The rates of risk-reducing mastectomy were statistically significantly higher in women with BRCA1 pathogenic variants than BRCA2, in women who had breast cancer than those who did not, in women with a breast cancer family history than in those without, in mothers than in those without children, in women who were receiving surveillance with MRI than those who were not and in women who received risk-reducing salpingo-oophorectomy than in those who did not on univariate analyses. The ages when they received the genetic testing were statistically significantly younger in the women receiving risk-reducing mastectomy than those who did not receive it. The women with BRCA1 pathogenic variants, personal history of breast cancer, mothers, those receiving MRI surveillance and younger women were independently significantly more likely to receive risk-reducing mastectomy based on multivariate analysis. CONCLUSIONS: The rate of risk-reducing mastectomy was not high in Japan; however, risk-reducing surgery was approved by the Japanese National Medical Insurance for hereditary breast and ovarian cancer patients with breast and/or ovarian cancer in 2020, so this rate will increase.

A practical survey of fertility-preservation treatments in the startup phase in Japan.

AIM: The actual status of fertility preservation treatments in the startup phase in Japan was investigated as a basis for discussing future directions. METHODS: This study was conducted as "Research project to promote support of children and parenting 2016" which was supported by Ministry of Health in Japan with the approval of the institutional review board at St. Marianna University. Subjects of the survey were facilities registered with the Japan Society of Obstetrics and Gynecology as fertility preservation facilities, and facilities belonging to the Japan Association of Private Assisted Reproductive Technology Clinics and Laboratories. We provided questionnaires to survey both the medical care system and cases for which fertility preservation was implemented between 2006 and 2016. RESULTS: Responses were obtained from 68 facilities (of the 64, 59 [92.2%] responded to the questionnaire and 9 clinics cooperated). Many facilities limited the cryopreservation of oocytes and ovaries to patients 40-41 years old and the use of eggs to patients 44-45 years old. In the patient survey, 812 cases of oocyte cryopreservation and 201 cases of ovarian tissue cryopreservation were performed during study period. Breast cancer was the most indicated disease, with oocyte cryopreservation in the late 30s and ovarian tissue cryopreservation in the early 30s. Very few babies were born from fertility preservation, and no live birth cases of ovarian tissue cryopreservation were identified. CONCLUSIONS: Even from the early days, fertility preservation was implemented according to certain standards in Japan, but was characterized by a large variety of facilities.

The possible effects of the Japan Society of Clinical Oncology Clinical Practice Guidelines 2017 on the practice of fertility preservation in female cancer patients in Japan.

Purpose: In 2017, the first guidelines for fertility preservation in cancer patients were published in Japan. However, the impact of the guidelines remains unknown. Therefore, the authors conducted a nationwide survey on cryopreservation procedures in the period from shortly before to after publication of the guidelines (2016-2019) and compared the results with our previous survey (2011-2015). The authors also surveyed reproductive specialists' awareness of the guidelines and implementation problems. Methods: The authors sent a questionnaire to 618 assisted reproductive technology facilities certified by the Japanese Society of Obstetrics and Gynecology. Results: The authors received responses from 395 institutions (63.8%). Among them, 144 institutions conducted cryopreservation for cancer patients (vs. 126 in 2011-2015) and performed 2537 embryo or oocyte and 178 ovarian tissue cryopreservation procedures (vs. 1085 and 122, respectively). Compared with the previous period, indications were more varied and protocols for controlled ovarian stimulation were more standardized. Reproductive specialists' interest in oncofertility was high, but many reported three main difficulties: selecting a treatment method, storing samples in the long term, and securing the necessary human resources. Conclusions: The practice of fertility preservation in cancer patients in Japan has been considerably affected by the first Japanese guidelines.

Zosteriform skin metastasis caused by retrograde lymphatic migration of metastatic squamous cell lung carcinoma.

BACKGROUND: Zosteriform skin metastasis (ZSM) is rare, and its etiology is not well understood. ZSM is possibly derived from the retrograde movement of cancer cells through the lymphatic vessels during disease development. However, it has been difficult to demonstrate it, as no specific findings have been observed. CASE PRESENTATION: A 68-year-old man presented to our department with neck lymphadenopathy. After detailed examinations, squamous cell lung carcinoma (cT2aN3M1c) was diagnosed. Although cisplatin combined with gemcitabine was administered, his cancerous lymphangiopathy was exacerbated, and ZSM was observed on his right chest. Pembrolizumab was initiated as a second-line chemotherapy; however, the patient died 7 months after the initial presentation. In this case, fluorodeoxyglucose-positron emission tomography indicated the presence of skin metastasis and cancerous lymphangiopathy. Similarly, after performing an autopsy, tumor-cell filled lymph ducts were observed in the right subclavian and the cutaneous lymphatic vessel from the right hilar lymph nodes. CONCLUSIONS: To the best of our knowledge, this is the first study to demonstrate that the localization of ZSM in the cutaneous lymphatics was caused by the retrograde movement of cancer cells through the lymphatic vessels, using radiographical and pathological analysis. In addition, fluorodeoxyglucose-positron emission tomography may help predict skin metastasis induced by cancerous lymphangiopathy.

Contribution of Pyk2 pathway and reactive oxygen species (ROS) to the anti-cancer effects of eicosapentaenoic acid (EPA) in PC3 prostate cancer cells.

BACKGROUND: n-3 polyunsaturated fatty acids (n-3 PUFAs), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are thought to exert protective effects in cardiovascular diseases. In addition, n-3 PUFAs have demonstrated anti-cancer effects in vitro and in vivo. OBJECTIVE: We investigated the anti-cancer effects and mechanism of action of EPA on PC3 prostate cancer cells in vitro. METHODS: PC3 cells were treated with various concentrations of EPA, and cell survival and the abilities of migration and invasion were evaluated. The time course of the growth inhibitory effect of EPA on PC3 cells was also assessed. The mechanism underlying the anti-cancer effects of EPA was investigated by human phosphokinase and human apoptosis antibody arrays, and confirmed by western blot analysis. We also examined the contribution of reactive oxygen species (ROS) to the effects of EPA using the ROS inhibitor N-acetyl cysteine. RESULTS: EPA decreased the survival of PC3 cells in a dose-dependent manner within 3 h of application, with an effective concentration of 500 µmol/L. EPA inhibited proline-rich tyrosine kinase (Pyk)2 and extracellular signal-regulated kinase 1/2 phosphorylation as determined by western blotting and the antibody arrays. The growth of PC3 cells was inhibited by EPA, which was dependent on ROS induction, while EPA inhibited Pyk2 phosphorylation independent of ROS production. CONCLUSIONS: Inhibition of Pyk2 phosphorylation and ROS production contribute to the anticancer effects of EPA on PC3 cells.

Recognition and attitudes of Japanese hematologists on sperm banking before chemotherapy: present status from nationwide questionnaire survey.

BACKGROUND: Treatment advancements have improved young cancer patients' survival rate considerably. Fertility preservation has become a very important tool in the prevention of treatment-induced gonadal toxicity. This study aimed to examine hematologists' awareness of its necessity and importance. METHODS: Questionnaires were mailed to the directors of 230 institutes that treated hematological malignancies in adults. The directors were asked to provide information regarding their institutes, collaboration with sperm banks, the number of patients treated per year, selection criteria for patients providing information, and their awareness of and attitudes toward sperm preservation. RESULTS: The response rate was 40.0%. Municipal and private hospitals treated patients significantly less frequently relative to university hospitals (p = .002). Of the 92 participating hematology institutions, 17 included sperm banks and 69 collaborated with sperm banks in neighboring institutions. Many participants stated that sperm preservation should be performed before chemotherapy; however, only 38% provided sperm preservation information to all patients. Participants in facilities without sperm banks exhibited significantly lower levels of knowledge regarding sperm preservation, relative to those from institutions with sperm banks, and found discussing fertility preservation burdensome. This trend was identical to that observed in a survey conducted 10 years earlier. CONCLUSION: Many hematologists did not appear to possess sufficient knowledge regarding fertility preservation. Moreover, few institutions included sperm banks, and a considerable burden was exerted on hematologists. The introduction of support systems is required to promote sperm preservation before cancer treatment.

Regulation of B-lineage cells by caspase 6.

The caspase (Casp) family of proteases regulate both lymphocyte apoptosis and activation. Here, we show that Casp6 regulates early B-cell development. One-week-old Casp6 knockout (Casp6 KO) mice have significantly more splenic B-cell subsets than wild-type (WT) mice. Adult Casp6 KO mice have normal levels of total splenic B cells but have increased numbers of B1a B cells and CD43+ "transitional" or splenic red pulp (RP) B cells. These results suggested that Casp6 may function to control B-cell numbers under nonhomeostatic conditions and during B-cell development. Consistent with this model, reconstitution of B cells was dysregulated in Casp6 KO mice after sublethal irradiation. Furthermore, bone marrow pro-B, pre-B and immature B-cell numbers were significantly higher in 1-week-old Casp6 KO mice than in 1-week-old WT mice. Casp6 KO pro-B cells proliferated more in response to IL-7 than WT pro-B cells, suggesting that Casp6 regulates early B-cell responses to IL-7. Indeed, adult and aged Casp6 KO mice had elevated numbers of IL-7αR+ Sca1+ precursors of common lymphoid progenitors, suggesting Casp6 may help regulate progenitors of B cells and early B-lineage cells. Casp6 regulates B-cell programs both during early development and after antigen stimulation in the periphery.

Correction: Genetic and clinical characteristics in Japanese hereditary breast and ovarian cancer: first report after establishment of HBOC registration system in Japan.

Correction to: Journal of Human Genetics advance online publication, 08 November 2017; https://doi.org/10.1038/s10038-017-0355-1.

Genetic and clinical characteristics in Japanese hereditary breast and ovarian cancer: first report after establishment of HBOC registration system in Japan.

The hereditary breast and ovarian cancer (HBOC) registration system of Japan was established by the Japanese HBOC Consortium. The first trial was registered in 2015 in four institutions to which some registration committee members belonged. We analyzed the information of 830 Japanese pedigrees, who underwent BRCA1/2 genetic testing, including mutation carriers with BRCA1 (N = 127) and BRCA2 (N = 115), and their families. The mutation-positive rate was 19.7%. Variants of uncertain significance were found in 6.5% of all individuals subjected to genetic testing for BRCA1/2. Compared to the United States, Japan had a higher mutation-positive rate in most categories, except for the groups with male breast cancer. Among the intrinsic subtypes of BRCA1-associated breast cancers, 75.8% were triple-negative. The incidence rate of contralateral breast cancer in BRCA1/2 mutation carriers was 0.99%/year. Among 240 mutation carriers, 26 and 62 patients underwent risk-reducing mastectomy (RRM) and risk-reducing salpingo-oophorectomy (RRSO), respectively; the respective frequencies of occult cancer were 7.1 and 3.2%. Metachronous breast cancer after RRM or peritoneal cancer after RRSO was not observed during the follow-up period. The nationwide registration system began last year and the system enables follow-up analysis in Japan.

Mechanical insights into jawbone characteristics under chronic kidney disease: A comprehensive nanoindentation approach.

The mechanical properties of the jawbone play a critical role in determining the successful integration of dental prostheses. Chronic kidney disease (CKD) has been identified to abnormally accelerate bone turnover rates. However, the impact of CKD on the mechanical characteristics of the jawbone has not been extensively studied. This study sought to evaluate the time-dependent viscoelastic behaviors of rat jawbones, particularly in the scenarios both with and without CKD. We hypothesized that CKD might compromise the bone's innate toughening mechanisms, potentially owing to the time-dependent viscoelasticity of the bone matrix proteins. The maxillary and mandibular bones of Wistar rats were subjected to nanoindentation and Raman micro-spectroscopy. Load-hold-displacement curves from the cortical regions were obtained via nanoindentation and were mathematically characterized using a suitable viscoelastic constitutive model. Raman micro-spectroscopy was employed to identify nuanced vibrational changes in local molecular structures induced by CKD. The time course of indenter penetration onto cortical bones during the holding stage (creep behavior) can be mathematically represented by a series arrangement of the Kelvin-Voigt bodies. This configuration dictates the overall viscoelastic response observed during nanoindentation tests. The CKD model exhibited a reduced extent of viscoelastic contributions, especially during the initial ramp loading phase in both the maxillary and mandibular cortical bones. The generalized Kelvin-Voigt model comprises 2 K-Voigt elements that signify an immediate short retardation time (τ1) and a subsequent prolonged retardation time (τ2), respectively. Notably, the mandibular CKD model led to an increase in the delayed τ2 alongside an increase in non-enzymatic collagen cross-linking. These suggest that, over time, CKD diminishes the bone's capability for supplementary energy absorption and dimensional recovery, thus heightening their susceptibility to fractures.

Chronic kidney disease compromises structural and mechanical properties of maxillary cortical bone in a rat model.

PURPOSE: This study aimed to investigate the effects of chronic kidney disease (CKD) on the structural and mechanical properties of the maxillary and mandibular cortical bone. METHODS: The maxillary and mandibular cortical bones from CKD model rats were used in this study. CKD-induced histological, structural, and micro-mechanical alterations were assessed using histological analyses, micro-computed tomography (CT), bone mineral density (BMD) measurements, and nanoindentation tests. RESULTS: Histological analyses indicated that CKD caused an increase in the number of osteoclasts and a decrease in the number of osteocytes in the maxilla. Micro-CT analysis revealed that CKD induced a void volume/cortical volume (%) increase, which was more remarkable in the maxilla than in the mandible. CKD also significantly decreased the BMD in the maxilla. In the nanoindentation stress-strain curve, the elastic-plastic transition point and loss modulus were lower in the CKD group than that in the control group in the maxilla, suggesting that CKD increased micro fragility of the maxillary bone. CONCLUSIONS: CKD affected bone turnover in the maxillary cortical bone. Furthermore, the maxillary histological and structural properties were compromised, and micro-mechanical properties, including the elastic-plastic transition point and loss modulus, were altered by CKD.

Annual report of the Japanese Breast Cancer Registry for 2019.

This is an annual report by the Japanese Breast Cancer Society regarding the clinical data on breast cancer extracted from the National Clinical Database-Breast Cancer Registry (NCD-BCR) of Japan. Here, we present an updated summary of 98,300 breast cancer cases registered in 2019. The median age at cancer diagnosis was 61 years (interquartile range 49-72 years), and 30.6% of the breast cancer patients were premenopausal. Of the 93,840 patients without distant metastases, 14,118 (15.0%) and 42,047 (44.8%) were diagnosed with stage 0 and I disease, respectively. Breast-conserving surgery was performed in 42,080 (44.8%) patients. Regarding axillary procedures, 62,677 (66.8%) and 7371 (7.9%) patients underwent sentinel node biopsy and axillary node dissection after biopsy, respectively. Whole breast irradiation was administered to 29,795 (70.8%) of the 42,080 patients undergoing breast-conserving surgery. Chest wall irradiation was administered to 5524 (11.1%) of the 49,637 patients who underwent mastectomy. Of the 6912 clinically lymph node-negative patients who received preoperative therapy, 5250 (76.0%) and 427 (6.2%) underwent sentinel node biopsy and axillary node dissection after biopsy, respectively; however, 602 (8.7%) patients initially underwent axillary node dissection without biopsy.

2020 Annual Report of National Clinical Database-Breast Cancer Registry: 10-year mortality of elderly breast cancer patients in Japan.

The Japanese Breast Cancer Society initiated the breast cancer registry in 1975, which transitioned to the National Clinical Database-Breast Cancer Registry in 2012. This annual report presents data from 2020 and analyzes the ten-year mortality rates for those aged 65 and older. We analyzed data from 93,784 breast cancer (BC) cases registered in 2020 and assessed 10-year mortality rates for 36,279 elderly patients diagnosed between 2008 and 2012. In 2020, 99.4% of BC cases were females with a median age of 61. Most (65%) were diagnosed at early stages (Stage 0 or I). Breast-conserving surgery rates varied with stages: 58.5% at cStage I, 30.8% at cStage II, and 13.1% at cStage III. Sentinel lymph node biopsy was done in 73.6% of cases, followed by radiotherapy in 70% of those post-conserving surgery and chemotherapy in 21.1% post-surgery. Pathology showed that 63.4% had tumors under 2.0 cm, 11.7% had pTis tumors, and 77.3% had no axillary lymph node metastasis. ER positivity was seen in 75.1%, HER2 in 14.3%, and 30% had a Ki67 positivity rate above 30%. Across all stages and subtypes, there was a trend where the 10-year mortality rates increased for individuals older than 65 years. In Stage I, many deaths were not directly linked to BC and, for those with HER2-type and triple-negative BC, breast cancer-related deaths increased with age. Within Stage II, patients older than 70 years with luminal-type BC often experienced deaths not directly linked to BC, whereas patients below 80 years with HER2-type and triple-negative BC, likely had breast cancer-related deaths. In Stage III, breast cancer-related deaths were more common, particularly in HER2 and triple-negative BC. Our prognostic analysis underscores distinct mortality patterns by stage, subtype, and age in elderly BC patients. It highlights the importance of personalized treatment strategies, considering subtype-specific aggressiveness, age-related factors, and comorbidities.

Survival trends and patient characteristics between 2004 and 2016 for breast cancer in Japan based on the National Clinical Database-Breast Cancer Registry.

This is a prognostic report by the Japanese Breast Cancer Society on breast cancer extracted from the National Clinical Database-Breast Cancer Registry of Japan. Here, we present a summary of 457,878 breast cancer cases registered between 2004 and 2016. The median follow-up duration was 5.6 years. The median age at the start of treatment was 59 years (5-95%: 38-82 years) and increased from 57 years between 2004 and 2008 to 60 years between 2013 and 2016. The proportion of patients with Stage 0-II disease increased from 74.5% to 78.3%. The number of cases with estrogen and progesterone receptor positivity increased from 74.8% to 77.9% and 60.5% to 68.1%, respectively. Regarding (neo-)adjuvant chemotherapy, the taxane (T) or taxane-cyclophosphamide (C) regimen increased by 2.4% to 8.2%, but the (fluorouracil (F)) adriamycin (A)-C-T/(F) epirubicin (E)C-T and (F)AC/(F)EC regimens decreased by 18.6% to 15.2% and 13.5% to 5.0%, respectively. Regarding (neo-)adjuvant anti-human epidermal growth factor-2 (HER2)-targeted therapy, the use of trastuzumab increased from 4.6% to 10.5%. The rate of sentinel lymph node biopsy increased from 37.1% to 60.7%, while that of axillary dissection decreased from 54.5% to 22.6%. Improvements in disease-free and overall survival were observed in patients with HER2-positive breast cancer, but there was no apparent trend in patients with hormone receptor-positive, HER2-negative, or triple-negative breast cancers.

Validation of the Japanese version of the Fatigue Barriers Scale (JFBS).

BACKGROUND: The Fatigue Barriers Scale (FBS) is an instrument to identify patient-derived barriers to fatigue management. OBJECTIVE: To assess the reliability and validity of the Japanese version of the FBS (JFBS). METHODS: Participants were 112 cancer patients. Reliability was determined through internal consistency using Cronbach's alpha coefficient and through test-retest reliability using Spearman's intra-class correlation coefficient (ICC). Construct, convergent, criterion-referenced, and concurrent validities were assessed. The Cancer Fatigue Scale (CFS), Patient Fatigue Knowledge Tool (PFKT), and Kessler 6-item distress scale (K6) were used for comparisons. RESULTS: Cronbach's alpha coefficients were 0.74, 0.78, 0.72, and 0.54 for the JFBS total and for each subscale, respectively. All ICCs exceeded 0.65 (P<0.05). The JFBS had a weak negative correlation with the PFKT and a positive correlation with the CFS. The K6 scores showed weak positive correlations with the JFBS total and fatalism subscale scores. CONCLUSIONS: The JFBS can be used to measure fatigue barriers in Japanese people with cancer.

Radiographic predictive factors for 10-year survival of removable partial denture abutment teeth: Alveolar bone level and density.

PURPOSE: To determine postoperative periodontal and radiographic factors that predict the survival rates of abutments of removable partial dentures (RPDs). METHODS: Patients who wore RPDs for > 10 years and received supportive periodontal therapy were included. Periodontal examinations and radiographic assessments were conducted on 83 abutment teeth in 35 patients at baseline, and five years after RPD insertion. In addition to conventional factors, such as tooth mobility at 5 years, radiographic factors, such as the crown-root ratio (ΔCR ratio) and gray-level changes reflecting changes in alveolar bone density (ΔABD), were evaluated. The impact of the covariables on the 10-year survival of abutment teeth was estimated using a multivariate Cox regression model, considering multicollinearity. RESULTS: Patients were classified as having A2-B2 (45.7%) and B3-C2 (54.3%) tooth loss, according to the Eichner classification. A probing depth ≥ 4 mm, tooth mobility ≥ grade 1, and CR ratio ≥ 1 were found in 30.1%, 33.7%, and 51.8% of abutment teeth, respectively. The 10-year survival rate of abutment teeth was 86.7%. Multivariate analysis showed that the 10-year survival of abutment teeth was significantly associated with root canal treatment (P = 0.045, hazard ratio [HR] = 1.23), the 5-year ΔCR ratio (P = 0.022, HR = 3.20), and ΔABD on the edentulous side of the abutment teeth (P = 0.047, HR = 1.08). CONCLUSIONS: In addition to root canal treatment, changes in the CR ratio and radiographic alveolar bone density at five years predicted the long-term survival rate of RPD abutments.

Targeting cellular gaps using Janus nanoparticles containing cationic polymers and surfactant lipids.

Since nanoparticles are taken up into cells by endocytosis, phagocytosis, or pinocytosis, they have been studied as intracellular drug carriers. Janus particles have an anisotropic structure composed of two or more distinct domains and have been proposed for use in various applications, including use as imaging agents or nanosensors. This study aimed to clarify the influence of the type of nanoparticles on their distribution in a human Caucasian colon adenocarcinoma (Caco-2) cell monolayer. We fabricated Janus and conventional spherical nanoparticles composed of pharmaceutically applicable ingredients. Janus and spherical nanoparticles composed of a cationic polymer and surfactant lipids were prepared by controlling the solvent removal pattern from the oil phase in the solvent removal process using the solvent evaporation and solvent diffusion methods. The distribution of nanoparticles in the Caco-2 cell monolayer was then evaluated using confocal laser microscopy. The mean hydrodynamic size of the fabricated Janus nanoparticles was 119.2 ± 4.6 nm. Distribution analysis using Caco-2 cells suggested that Janus nanoparticles were localized around the adherens junctions located just below the tight junction. Clear localization was not observed in non-Janus nanoparticles with the same composition. The clear localization of the Janus nanoparticles around the adherens junction may be due to their positive charge and asymmetric structure. Our results suggest the considerable potential for the development of nanoparticulate drug carriers to target cellular gaps.

Caco-2 Cell Sheet Partially Laminated with HT29-MTX Cells as a Novel In Vitro Model of Gut Epithelium Drug Permeability.

The intestinal epithelial Caco-2 cell monolayer is a well-established in vitro model useful for predicting intestinal drug absorption in humans. Coculture models of Caco-2 and goblet-cell-like HT29-MTX cells have been developed to overcome the lack of a mucus layer; however, those models are much leakier compared to the intestinal epithelium. Here, we developed a partially laminated culture model where HT29-MTX cells were superimposed onto a Caco-2 monolayer to overcome this issue. A morphological study showed that the piled HT29-MTX cells were voluntarily incorporated into the Caco-2 monolayer, and mucus production was confirmed via periodic acid-Schiff and mucin protein 2 staining. Permeability was evaluated in terms of transepithelial electrical resistance (TEER) and the apparent permeability of paracellular markers with different molecular sizes. The partially laminated model maintained the high barrier function of the Caco-2 monolayer, whose permeability appeared adjustable according to the HT29-MTX/Caco-2 cell ratio. In contrast, the coculture models showed abnormally high permeability of those markers, correlated with low TEER. Thus, the partially laminated model enabled in vitro recapitulation of effective mucosal barrier function. Consequently, this novel model may be useful as an in vitro high-throughput evaluation system for enteral mucosal permeability and mucus-penetrating efficiency of drugs and nanocarriers.