Protecting-Group-Free Synthesis of ADP-Ribose and Dinucleoside Di-/Triphosphate Derivatives via P(V)-P(V) Coupling Reaction.

Biomolecules containing adenosine di- or triphosphate (ADP or ATP) are crucial for diverse biological processes. Synthesis of these biomolecules and development of their chemical probes are important to elucidate their functions. Enabling reproducible and high-yielding access to these ADP- and ATP-containing molecules via conventional P(III)-P(V) and P(V)-P(V) coupling reactions is challenging owing to water content in highly polar phosphate-containing substrates. Herein, we report an efficient and reliable method for protecting-group-free P(V)-P(V) coupling reaction through in situ activation of phosphates using hydrolysis-stable 2-[N-(2-methylimidazoyl)]-1,3-dimethylimidazolinium chloride (2-MeImIm-Cl), providing the corresponding electrophilic P(V) intermediates for subsequent nucleophilic attack using their coupling partners. This P(V)-P(V) coupling reaction proceeded even in a wet reaction medium and showed a broad substrate scope, accommodating protecting-group-free synthesis of ADP-ribose and nicotinamide adenine diphosphate analogs, ATP-containing biomolecules, and ADP-ribosyl peptides.

Trends in incidence and hormonal management of endometrial cancer during potentially reproductive age in Japan: a population-based study.

BACKGROUND: We aimed to investigate the trends in the incidence and treatment of endometrial cancer (EC) during potentially reproductive age in Japan, with a special focus on the relative oncologic safety of hormonal therapy (HT) over surgery. METHODS: This population-based retrospective cohort study was conducted using data from the Osaka Cancer Registry from 2004 to 2018. Women with EC were first identified and then distributions of age, stage, histology, and initial treatment were examined. Then, the relative oncologic safety of HT over surgery in patients under the age of 50 years was evaluated. RESULTS: Among the 9417 patients with EC, 1937 were diagnosed during their potentially reproductive age (< 50 years). The incidence of EC during potentially reproductive age has increased from 18.5% in 2004-2011 to 21.9% in 2012-2018. ECs during potentially reproductive age more frequently displayed favorable characteristics, such as endometrioid histology, and lower histological grade than those in non-potentially reproductive age. Among the 1223 patients diagnosed with localized endometrioid EC, 74 cases (6.0%) received HT as an initial treatment, while 1100 cases (90.0%) underwent surgery as their initial treatment. When the two treatment groups were compared, there was no significant difference in overall survival (p = 0.3713). The estimated 5-year survival rates were 100 and 98.8% in the HT and surgery groups, respectively. CONCLUSION: EC is increasingly diagnosed during potentially reproductive age in Japan. The use of HT as an initial treatment is increasing, and achieved comparable survival outcomes to urgery against localized endometrioid EC during the potentially reproductive age.

Recent progress in the synthesis of glycosphingolipids.

To accelerate the biological study and application of the diverse functions of glycosphingolipids (GSLs), the production of structurally defined GSLs has been greatly demanded. In this review, we focus on the recent developments in the chemical and chemoenzymatic synthesis of GSLs. In the chemical synthesis section, the syntheses based on glucosyl ceramide cassette, late-stage sialylation, and diversity-oriented strategies for GSLs or ganglioside synthesis are highlighted, which delivered terpioside B, fluorescent sialyl lactotetraosyl ceramide, and analogs of lacto-ganglio-series GSLs, respectively. In the chemoenzymatic synthesis section, the synthesis of ganglioside GM1 by multistep one-pot multienzyme method and the total synthesis of highly complex ganglioside LLG-5 using a water-soluble lactosyl ceramide as a key substrate for enzymatic sialylation are described.

Convergent synthesis of functionalized derivatives of stage-specific embryonic antigens 3 & 4.

Stage-specific embryonic antigens (SSEAs) are carbohydrate markers that have diverse roles in embryonic development. However, the exact roles of SSEAs remain unclear. To obtain mechanistic insights into their roles, we aimed to develop functionalized SSEA glycan analogs via chemical synthesis. Herein, we report a convergent synthetic approach for SSEA-3 and SSEA-4 analogs using readily available versatile building blocks. A key step, namely the stereoselective glycosylation of a common tetrasaccharide acceptor, was successfully achieved using a 4-O-Bn Gal donor for SSEA-3 and a Neu-Gal donor for SSEA-4, which were previously developed by our group. The obtained SSEA-3 and SSEA-4 glycans were further functionalized with biotin and deuterated lipid for applications in biological studies. Thus, the findings of this study will facilitate further research on SSEAs.

Twenty-five-year mortality trends of four major histological subtypes of cervical cancer: a population-based study using the Osaka cancer registry data.

Objective: To assess the mortality trends of four major histological subtypes of cervical cancer diagnosed between 1994 and 2018. Methods: This population-based retrospective cohort study was conducted using the Osaka Cancer Registry data from 1994 to 2018. A total of 12,003 patients with cervical cancer, squamous cell carcinoma (SCC), adenocarcinoma (A), adenosquamous cell carcinoma (AS), or small cell neuroendocrine carcinoma (SCNEC) were identified. Patients were classified into groups according to the extent of disease (localized, regional, or distant), year of diagnosis (1994-2002, 2003-2010, or 2011-2018), and histological subtype (SCC, A/AS, or SCNEC). Then, their survival rates were assessed using univariate and multivariate analyses. Results: Overall, improved survival rates were observed according to the year of diagnosis in patients with local, regional, and distant cervical cancers. When examined according to the histological subtypes, improved survival rates according to the year of diagnosis were observed in patients with local, regional, and distant SCCs and in those with local and regional A/AS. In patients with distant A/AS, the survival rates did not improve since 2003. In patients with cervical cancer with SCNEC, the survival rates did not improve since 1994 irrespective of the extent of the disease. In the multivariate analysis, non-SCC histology was found to be an independent prognostic factor for OS. Conclusion: In contrast to SCC histology associated with improved survival between 1994 and 2018, SCNEC histology and advanced (stage IVB) A/AS remain to be the unmet medical needs for the management of cervical cancer.

Population-Based Survival Analysis of Stage IVB Small-Cell Neuroendocrine Carcinoma in Comparison to Major Histological Subtypes of Cervical Cancer.

The aim of the current study is to investigate the survival outcome of stage IVB SCNEC of the uterine cervix in comparison to major histological subtypes of cervical cancer. A population-based retrospective cohort study was conducted using the Osaka Cancer Registry data from 1994 to 2018. All FIGO 2009 stage IVB cervical cancer patients who displayed squamous cell carcinoma (SCC), adenocarcinoma (A), adenosquamous cell carcinoma (AS), or small-cell neuroendocrine carcinoma (SCNEC) were first identified. The patients were classified into groups according to the types of primary treatment. Then, their survival rates were examined using the Kaplan-Meier method. Overall, in a total of 1158 patients, clearly differential survival rates were observed according to the histological subtypes, and SCNEC was associated with shortest survival. When examined according to the types of primary treatments, SCNEC was associated with significantly decreased survival when compared to SCC or A/AS, except for those treated with surgery. In patients with FIGO 2009 stage IVB cervical cancer, SCNEC was associated with decreased survival when compared to SCC or A/AS. Although current treatments with either surgery, chemotherapy or radiotherapy have some therapeutic efficacies, to improve the prognosis, novel effective treatments specifically targeting cervical SCNEC need to be developed.

Comparison of the Survival Outcomes of Minimally Invasive Surgery with Open Surgery in Patients with Uterine-Confined and Node-Negative Cervical Cancer: A Population-Based Study.

We aimed to compare the oncological outcomes between Japanese women with uterine-confined and node-negative cervical cancer who underwent open surgery and those who underwent minimally invasive surgery (MIS). A population-based retrospective cohort study was conducted using data from the Osaka Cancer Registry that ranged from 2011 to 2018. A total of 2279 patients who underwent surgical treatment for uterine-confined and node-negative cervical cancer were identified. The patients were classified into groups according to surgery type (open and MIS groups) and year of diagnosis (group one, 2011-2014; group two, 2015-2018). The oncologic outcomes were compared between the MIS and open groups. When the MIS group (n = 225) was compared with open group (n = 2054), overall, there was no significant between-group difference in terms of overall survival. Based on Kaplan-Meier estimates, the probability of overall survival at four years was 99.5% in the MIS group and 97.2% in the open group (p = 0.1110). When examined according to the year of diagnosis, there were no significant between-group differences in the overall survival in both groups one and two. In this population-based cohort study, MIS did not compromise survival outcomes when compared with conventional open surgery in Japanese patients with uterine-confined and node-negative (FIGO 2018 stage I) cervical cancer.

Evaluation of survival outcomes between minimally invasive and open surgery in the treatment of early-stage endometrial cancer: a population-based study in Osaka Japan.

OBJECTIVE: To compare the oncological outcomes between Japanese women who underwent minimally invasive surgery and those who underwent open surgery for early-stage endometrial cancer. METHODS: This population-based retrospective cohort study was conducted using data from the Osaka Cancer Registry from 2011 to 2018. Surgically treated patients for localized (uterine-confined) endometrial cancer were identified. Patients were classified into two groups according to the type of surgery (minimally invasive surgery group and open-surgery group), pathological risk factors (low-risk and high-risk), and year of diagnosis (Group 1, 2011-14; Group 2, 2015-18). Overall survival was compared between the minimally invasive surgery and open-surgery groups. RESULTS: In the analyses including all patients, there was no difference in overall survival between the minimally invasive surgery and open-surgery groups (P = 0.0797). The 4-year overall survival rate was 97.1 and 95.7% in the minimally invasive surgery and open-surgery groups, respectively. When investigated according to pathological risks, there were no differences in overall survival between the minimally invasive surgery and open-surgery groups in both the low- and high-risk groups. In the low-risk group, the 4-year overall survival rates in the minimally invasive surgery and open-surgery groups were 97.7 and 96.5%, respectively. In the high-risk group, the 4-year overall survival rates in the minimally invasive surgery and open-surgery groups were 91.2 and 93.2%, respectively. Similarly, there were no differences in overall survival between the minimally invasive surgery and open-surgery groups in both Group 1 (P = 0.4479 in low-risk and P = 0.1826 in high-risk groups) and Group 2 (P = 0.1750 in low-risk and P = 0.0799 in high-risk groups). CONCLUSION: Our study provides epidemiological evidence that minimally invasive surgery is an effective alternative to open surgery in Japanese patients with early-stage endometrial cancer.

Recently developed glycosphingolipid probes and their dynamic behavior in cell plasma membranes as revealed by single-molecule imaging.

Glycosphingolipids, including gangliosides, are representative lipid raft markers that perform a variety of physiological roles in cell membranes. However, studies aimed at revealing their dynamic behavior in living cells are rare, mostly due to a lack of suitable fluorescent probes. Recently, the ganglio-series, lacto-series, and globo-series glycosphingolipid probes, which mimic the behavior of the parental molecules in terms of partitioning to the raft fraction, were developed by conjugating hydrophilic dyes to the terminal glycans of glycosphingolipids using state-of-art entirely chemical-based synthetic techniques. High-speed, single-molecule observation of these fluorescent probes revealed that gangliosides were scarcely trapped in small domains (100 nm in diameter) for more than 5 ms in steady-state cells, suggesting that rafts including gangliosides were always moving and very small. Furthermore, dual-color, single-molecule observations clearly showed that homodimers and clusters of GPI-anchored proteins were stabilized by transiently recruiting sphingolipids, including gangliosides, to form homodimer rafts and the cluster rafts, respectively. In this review, we briefly summarize recent studies, the development of a variety of glycosphingolipid probes as well as the identification of the raft structures including gangliosides in living cells by single-molecule imaging.

Cell density-dependent membrane distribution of ganglioside GM3 in melanoma cells.

Monosialoganglioside GM3 is the simplest ganglioside involved in various cellular signaling. Cell surface distribution of GM3 is thought to be crucial for the function of GM3, but little is known about the cell surface GM3 distribution. It was shown that anti-GM3 monoclonal antibody binds to GM3 in sparse but not in confluent melanoma cells. Our model membrane study evidenced that monoclonal anti-GM3 antibodies showed stronger binding when GM3 was in less fluid membrane environment. Studies using fluorescent GM3 analogs suggested that GM3 was clustered in less fluid membrane. Moreover, fluorescent lifetime measurement showed that cell surface of high density melanoma cells is more fluid than that of low density cells. Lipidomics and fatty acid supplementation experiment suggested that monounsaturated fatty acid-containing phosphatidylcholine contributed to the cell density-dependent membrane fluidity. Our results indicate that anti-GM3 antibody senses GM3 clustering and the number and/or size of GM3 cluster differ between sparse and confluent melanoma cells.

Unprecedented neighboring group participation of C2 N-imidoxy functionalities for 1,2-trans-selective glycosylation.

Stereoselective glycosylation reactions are important in carbohydrate chemistry. The most used method for 1,2-trans(ß)-selective glycosylation involves the neighboring group participation (NGP) of the 2-O-acyl protecting group; nevertheless, an alternative stereoselective method independent of classical NGP would contribute to carbohydrate chemistry, despite being challenging to achieve. Herein, a ß-selective glycosylation reaction employing unprecedented NGP of the C2 N-succinimidoxy and phthalimidoxy functionalities is reported. The C2 functionalities provided the glycosylated products in high yields with ß-selectivity. The participation of the functionalities from the α face of the glycosyl oxocarbenium ions gives stable six-membered intermediates and is supported by density functional theory calculations. The applicability of the phthalimidoxy functionality for hydroxyl protection is also demonstrated. This work expands the scope of functionalities tolerated in carbohydrate chemistry to include O-N moieties.

Novel Strategy for the Management of Cervical Multicystic Diseases.

PURPOSE: To investigate the clinical practices of diagnosing multicystic cervical lesions as a means to develop a more appropriate diagnostic algorithm for gastric-type adenocarcinoma (GAS) and its precursors. METHODS: Clinical information for 159 surgically treated patients for multicystic disease of the uterine cervix was collected from 15 hospitals. We performed a central review of the MRI and pathological findings. The MRI findings were categorized into four types including two newly proposed imaging features based on the morphology and distribution of cysts, and the diagnosis accuracy was assessed. Among the four MRI types, types 1 and 2 were categorized as benign lesions that included LEGH; type 3 were precancerous lesions (with an assumption of atypical LEGH); and type 4 were malignant lesions. RESULTS: The central pathological review identified 56 cases of LEGH, seven with GAS, four with another form of carcinoma, and 92 with benign disease. In clinical practice, over-diagnosis of malignancy (suspicion of MDA) occurred for 12/19 cases (63.2%) and under-diagnosis of malignancy occurred for 4/11 (36%). Among the 118 patients who had a preoperative MRI and underwent a hysterectomy, type 3 or 4 MRI findings in conjunction with abnormal cytology were positively indicative of premalignancy or malignancy, with a sensitivity and specificity of 61.1% and 96.7%, respectively. CONCLUSIONS: Although the correct preoperative diagnosis of cervical cancer with a multicystic lesion is challenging, the combination of cytology and MRI findings creates a more appropriate diagnostic algorithm that significantly improves the diagnostic accuracy for differentiating benign disease from premalignancy and malignancy.

Fluorescent GD2 analog for single-molecule imaging.

Ganglioside GD2 is associated with the proliferation and migration of breast cancer cells. However, the precise role of GD2 is unclear because its tendency to form dynamic and transient domains in cell plasma membranes (PMs), called lipid rafts, makes it difficult to observe. Previously, we developed fluorescent analogs of gangliosides (e.g., GM3 and GM1), which enabled the observation of lipid raft formation for the first time using single-molecule imaging. In this report, we describe the first chemical synthesis of a fluorescent ganglioside, GD2. A biophysical analysis of the synthesized analog revealed its raft-philic character, suggesting its potential to aid single-molecule imaging-based investigations into raft-associated interactions.

Impact of lymphadenectomy in patients with locally recurrent or persistent cervical cancer treated with salvage hysterectomy.

AIM: To investigate the role of lymphadenectomy (LND) in locally recurrent or persistent cervical cancer patients treated with salvage hysterectomy. METHODS: Locally recurrent or persistent cervical cancer patients treated with salvage hysterectomy, with or without LND, were identified. Patients were divided into two groups according to the status of radiologic evidence of lymph node metastasis, and the impact of LND was investigated by evaluating postoperative survival. RESULTS: This study included 72 patients; 48 did not show radiological evidence of lymph node metastasis (Group 1) while 24 did (Group 2). Overall, the addition of LND to salvage hysterectomy resulted in increased postoperative complications. In Group 1, salvage hysterectomy plus LND resulted in the identification of five cases with false-negative lymph nodes (19.2%), but showed no advantage over salvage hysterectomy alone in terms of postoperative survival. In Group 2, all patients underwent LND, which resulted in the identification of eight cases with false-positive nodes (33.3%), and reasonably long postoperative survival. The estimated 3-year postoperative survival rate in this group was 39.7%. CONCLUSION: Including LND in salvage hysterectomy allows for precise lymph node staging but increases risk of postoperative complications. However, considering the inability to improve survival, LND should not be performed during salvage hysterectomy in patients without radiological evidence of lymph node metastasis. In patients with radiological evidence of lymph node metastasis, salvage hysterectomy plus LND can only be performed in those who understand the risk of postoperative complications and the limited evidence supporting its survival advantage.

Chemical synthesis of sialoglyco-architectures.

The synthesis of sialic acid-containing molecules has posed a formidable challenge to carbohydrate chemists for over 50 years. Our research group has intensively searched for robust chemistry to enable the construction of a broad spectrum of sialic acid-containing molecules to advance the understanding and application of their biological functions. Herein, we describe our research findings on the development of sialic acid donors for α-selective glycosidation and the chemical synthesis of sialic acid- containing molecules, with a special focus on gangliosides and their fluorescent probes.

Full Stereocontrol in α-Glycosidation of 3-Deoxy-d-manno-2-octulosonic Acid (Kdo) Using Macrobicyclic Glycosyl Donors.

We describe a method for the α-selective glycosidation of 3-deoxy-d-manno-2-octulosonic acid (Kdo) using a macrobicyclic Kdo donor as the precursor of a bridgehead oxocarbenium ion, whose stereoselectivity is not affected by the substrate structure and reaction conditions. Strapping Kdo via tethering in the α-configuration at the C1 and C5 positions completely blocked nucleophilic attack to the ß-face of the anomeric center by sterically hindering the bicyclic system, realizing full α-selectivity during glycosidation.

Disposition of E-selectin-targeting liposomes in tumor spheroids with a perfusable vascular network.

We constructed tumor spheroids with a perfusable vascular network to assess drug delivery systems that target the tumor vasculature. A tricultured tumor spheroid containing human umbilical vein endothelial cells (HUVECs) was placed in the central compartment of a microfluidic device, and the HUVECs were seeded into the microslit channels on both sides. Angiogenic sprouts began to form within a few days, from both the tumor spheroids and microchannels, and became more abundant and branched, while attracting each other, over time. A continuous vascular network of HUVECs was fully formed on Day 7. The uptake of 3'-(1-carboxy)ethyl sialyl Lewis X mimic (3'-CE sLeX mimic) liposomes, which have previously been proven to recognize E-selectin, in vascular-perfusable tumor spheroids was assessed. 3'-CE sLeX mimic and pegylated liposomes were rarely taken up, but when the vascular network was pretreated with TNF-α and IL-1ß, 3'-CE sLeX mimic liposomes accumulated considerably more in endothelial cells and their vicinity. Taken together, along with the known in vivo expression of E-selectin in tumor angiogenic blood vessels, these results suggest that 3'-CE sLeX mimic liposomes are a promising carrier for targeting tumor vasculature. Furthermore, proinflammatory cytokine treatment may be appropriate for use with vascular-perfusable tumor spheroids in pharmacokinetic studies.

Straightforward Synthesis of the Poly(ADP-ribose) Branched Core Structure.

Poly(ADP-ribosyl)ation is a post-translational modification that produces poly(ADP-ribose) with a branched structure every 20-50 units; such branching structure has been previously suggested to be involved in regulating chromatin remodeling. To elucidate its detailed functions, we developed a straightforward method for the synthesis of the poly(ADP-ribose) branched core structure, α-d-ribofuranosyl-(1‴ → 2″)-α-d-ribofuranosyl-(1″ → 2')-adenosine 5',5'',5‴-trisphosphate 1, from 6-chloropurine ribofuranoside 4 in 10 steps and 6.1% overall yield. The structure poses synthetic challenges for constructing iterative α-1,2-cis-glycosidic bonds in the presence of a purine base and the installation of three phosphate groups at primary hydroxyl groups. Iterative glycosidic bonds were formed by α-1,2-cis-selective ribofuranosylation using 2-O-(2-naphthylmethyl)-protected thioglycoside donor 6 and a thiophilic bismuth promoter. After the construction of diribofuranosyl adenosine 5 had been constructed, it was chemo- and regioselectively phosphorylated at a later stage. Subsequent deprotection provided the synthetic target 1.

Significance of the Number and the Location of Metastatic Lymph Nodes in Locally Recurrent or Persistent Cervical Cancer Patients Treated with Salvage Hysterectomy plus Lymphadenectomy.

We retrospectively investigated the significance of metastatic lymph nodes in patients with locally recurrent or persistent cervical cancer in a previously irradiated field and subsequently had salvage hysterectomy. Clinical data were obtained from a chart review, and the prognostic impact of the presence, number (1-2 versus ≥3), and location (pelvic versus pelvic plus para-aortic) of lymph node metastasis was investigated by comparing recurrence and survival. In total, 50 patients were included in this study, of which 21 (42.0%) showed pathological evidence of lymph node metastasis (node-positive group). Both the univariate and multivariate analyses showed that lymph node metastasis was an independent prognostic factor for postoperative recurrence (hazard ratio (HR) 5.36; 95% CI 1.41-6.66; p = 0.0020). The predominant sites of recurrence after salvage surgery were the visceral organs and lymph nodes in the node-negative and node-positive groups, respectively. Patients with ≥3 node metastases showed similar survival to those with 1-2 node metastases. Patients with pelvic node metastasis showed similar survival to those with pelvic and para-aortic node metastases. The presence, not number or location, of lymph node metastasis was an independent poor prognostic factor for post-operative recurrence in patients who developed locally recurrent or persistent cervical cancer treated with salvage hysterectomy plus lymphadenectomy.