Case Report: Longitudinal monitoring of clonal evolution by circulating tumor DNA for resistance to anti-EGFR antibody in a case of metastatic colorectal cancer.

Background: Treatment with anti-EGFR antibody has been shown to prolong survival in patients with RAS wild-type metastatic colorectal cancer (mCRC). However, even patients who initially respond to anti-EGFR antibody therapy, almost without exception, develop resistance to the therapy and then fail to respond. Secondary mutations in the mitogen-activated protein (MAPK) signaling pathway (mainly in NRAS and BRAF) have been implicated in anti-EGFR resistance. However, the process by which resistant clones develop during therapy has not been elucidated, and considerable intrapatient and interpatient heterogeneity exists. Circulating tumor DNA (ctDNA) testing has recently allowed the noninvasive detection of heterogeneous molecular alterations that underlie the evolution of resistance to anti-EGFR. In this report, we describe our observation of genomic alterations in KRAS and NRAS in a patient with acquired resistance to anti-EGFR antibody drugs by tracking clonal evolution using serial ctDNA anaylsis. Case presentation: A 54-year-old woman was initially diagnosed with sigmoid colon cancer with multiple liver metastases. After receiving first-line mFOLFOX + cetuximab, second-line FOLFIRI + ramucirumab, third-line trifluridine/tipiracil + bevacizumab, fourth-line regorafenib, and fifth-line CAPOX + bevacizumab, she was rechallenged with CPT-11 + cetuximab. The best response to anti-EGFR rechallenge therapy was a partial response. RAS in the ctDNA was assessed during treatment. The RAS status changed from wild type to mutant type, back to wild type, and again to mutant type (NRAS/KRAS codon 61) during the course of treatment. Conclusion: In this report, tracking of ctDNA allowed us to describe clonal evolution in a case in which we observed genomic alterations in KRAS and NRAS in a patient who acquired resistance to anti-EGFR antibody drugs during treatment. It is reasonable to consider repeat molecular interrogation during progression in patients with mCRC by using ctDNA analysis, which could help to identify patients who may benefit from a rechallenge strategy.

Hilar/mediastinal and cutaneous drug-induced sarcoidosis-like reaction associated with immune checkpoint inhibitors in metastatic colorectal cancer: a case report.

Background: Immune checkpoint inhibitors (ICIs) are the standard treatment for metastatic colorectal cancer (mCRC) with high microsatellite instability (MSI-H). Among immune-related adverse events (irAEs), drug-induced sarcoidosis-like reactions (DISR) are often difficult to differentiate from cancer progression. Main Body: This is a case of a woman in her mid-60s, with mCRC (RAS wild/BRAF mutant/MSI-H) and abdominal lymph node metastasis, treated with four courses of ipilimumab + nivolumab every 3 weeks, followed by nivolumab every 2 weeks as third-line treatment. After treatment, the original lymph node metastases shrank, but hilar/mediastinal lymph nodes appeared. Endoscopic ultrasound-guided fine-needle aspiration of these lymph nodes revealed multiple epithelioid granulomas without necrosis, indicating a sarcoidosis-like reaction. Fluorodeoxyglucose-positron emission tomography scan showed abnormal subcutaneous accumulation in bilateral forearms and bilateral knee joints. Biopsy of the cutaneous lesions was also performed, which revealed epithelioid granulomas. As the patient had no symptoms in other organs, no specific therapeutic intervention was administered. After the discontinuation of immunotherapy, the sarcoidosis-like reaction regressed without cancer relapse. Conclusions: Clinicians should be aware of the possibility of DISR as an irAE during the ICI treatment of mCRC. In suspected cases of DISR following ICI therapy, it is important to differentiate between cancer progression and DISR through histological diagnosis for the subsequent strategy, as radiological and serological findings are not definitive.

In Vitro and In Vivo Assessment of Atemoya Fruit (Annona atemoya) for Food-Drug Interactions.

BACKGROUND AND OBJECTIVES: Atemoya (Annona atemoya) is increasingly being consumed worldwide because of its pleasant taste. However, only limited information is available concerning possible atemoya-drug interactions. In the present study, the issue of whether atemoya shows food-drug interactions with substrate drugs of the major drug-metabolizing cytochrome P450s (i.e., CYP1A2, CYP2C9, and CYP3A) is addressed. METHODS: The ability of atemoya juice to inhibit the activities of phenacetin O-deethylase (CYP1A2), diclofenac 4'-hydroxylase (CYP2C9), and midazolam 1'-hydroxylase (CYP3A) was examined in vitro using human and rat liver microsomes. The in vivo pharmacokinetics of phenacetin and metabolites derived from it in rats when atemoya juice or fluvoxamine (a CYP1A2 inhibitor) was preadministered were also investigated. RESULTS: Atemoya juice significantly inhibited CYP1A2 activity in human liver microsomes, but not the activities of CYP2C9 and CYP3A. In spite of this inhibition, preadministration of atemoya had no effect on the pharmacokinetics of phenacetin, a CYP1A2 substrate, in rats. Meanwhile, preadministration of fluvoxamine significantly extended the time needed for the elimination of phenacetin, possibly due to the inhibition of CYP1A2. This suggests that the intake of an excess amount of atemoya juice is necessary to cause a change in the pharmacokinetics of phenacetin when the IC50 values for CYP1A2 inhibition by atemoya and fluvoxamine are taken into account. CONCLUSION: The results indicate that a daily intake of atemoya would not change the pharmacokinetics of CYP1A2 substrates such as phenacetin as well as CYP2C9- and CYP3A-substrate drugs.

Case series of three patients with hereditary diffuse gastric cancer in a single family: Three case reports and review of literature.

BACKGROUND: Hereditary diffuse gastric cancer (HDGC) is a familial cancer syndrome often associated with germline mutations in the CDH1 gene. However, the frequency of CDH1 mutations is low in patients with HDGC in East Asian countries. Herein, we report three cases of HDGC harboring a missense CDH1 variant, c.1679C>G, from a single Japanese family. CASE SUMMARY: A 26-year-old female (Case 1) and a 51-year-old male (father of Case 1), who had a strong family history of gastric cancer, were diagnosed with advanced diffuse gastric cancer. After genetic counselling, a 25-year-old younger brother of Case 1 underwent surveillance esophagogastroduodenoscopy that detected small signet ring cell carcinoma foci as multiple pale lesions in the gastric mucosa. Genetic analysis revealed a CDH1 c.1679C>G variant in all three patients. CONCLUSION: It is important for individuals suspected of having HDGC to be actively offered genetics evaluation. This report will contribute to an increased awareness of HDGC.

Clinical impact of primary tumour location, early tumour shrinkage, and depth of response in the treatment of metastatic colorectal cancer with first-line chemotherapy plus cetuximab or bevacizumab.

The primary tumour location is an important prognostic factor for previously untreated metastatic colorectal cancer (mCRC). However, the predictive efficacies of primary tumour location, early tumour shrinkage (ETS), and depth of response (DpR) on mCRC treatment has not been fully evaluated. This study aimed to investigate the predictive efficacies of these traits in mCRC patients treated with first-line 5-fluorouracil-based chemotherapy plus biologic agents, namely, cetuximab and bevacizumab. This was a retrospective analysis of the medical records of 110 patients with pathology-documented unresectable mCRC. Patients with left-sided mCRC receiving any first-line regimen showed better overall survival (OS) than those with right-sided mCRC [33.3 vs 16.3 months; hazard ratio (HR) 0.44; 95% confidence interval (CI) 0.27-0.74; p < 0.001]. In patients with left-sided tumours, treatment with chemotherapy plus cetuximab yielded longer OS than chemotherapy plus bevacizumab (50.6 vs 27.8 months, HR 0.55; 95% CI 0.32-0.97; p = 0.0378). mCRC patients with ETS and high DpR showed better OS than those lacking ETS and with low DpR (33.5 vs 19.6 months, HR 0.50, 95% CI 0.32-0.79, p = 0.023 and 38.3 vs 19.0 months, HR 0.43, 95% CI 0.28-0.68, p < 0.001, respectively). Moreover, ETS and/or high DpR achieved in patients with right-sided mCRC receiving chemotherapy plus cetuximab were associated with significantly better OS than in those lacking ETS and with low DpR (34.3 vs 10.4 months, HR 0.19, 95% CI 0.04-0.94, p = 0.025 and 34.3 vs 10.4 months, HR 0.19, 95% CI 0.04-0.94, p = 0.0257, respectively). Taken together, our study demonstrates that primary tumour location is not only a well-known prognostic factor but also a relevant predictive factor in patients with mCRC receiving chemotherapy plus cetuximab. Additionally, both ETS and DpR could predict treatment outcomes and also potentially guide cetuximab treatment even in right-sided mCRCs.

Hyperemesis-induced Wernicke-Korsakoff Syndrome due to Hypergastrinemia during Long-term Treatment with Proton Pump Inhibitors.

We herein report a patient with Wernicke-Korsakoff syndrome (WKS) who had neither a history of alcoholism or of history of gastric surgery. A 56-year-old woman was transferred to our hospital because of the loss of consciousness and she was diagnosed to have Wernicke encephalopathy. She showed proton pump inhibitor-induced refractory hypergastrinemia with the subsequent development of hyperemesis and a vitamin B1 deficiency.

Maturation and Phenotypic Heterogeneity of Human CD4+ Regulatory T Cells From Birth to Adulthood and After Allogeneic Stem Cell Transplantation.

CD4+ Regulatory T cells (Treg) play a critical role in maintaining immune homeostasis. Various Treg subsets have been identified, however the heterogeneity of Treg subpopulations during development remains uncharacterized. Using mass cytometry we obtained single cell data on expression of 35 functional markers to examine the heterogeneity of Treg cells at birth and in adults. Unsupervised clustering algorithms FlowSOM and ACCENSE were used to quantify Treg heterogeneity. As expected, Treg in umbilical cord blood were predominately naïve while Treg in adult blood were predominately central memory and effector memory cells. Although umbilical cord blood Treg are mostly naïve cells, we observed multiple phenotypic Treg subsets in cord blood. Nevertheless, peripheral blood in adults contained higher percentages of Treg and the heterogeneity of Treg was significantly increased in adults. We also studied Treg heterogeneity throughout a 2-year period after allogeneic hematopoietic stem cell transplantation (alloHSCT) and in patients with chronic graft-versus-host disease (cGVHD). Treg heterogeneity recovered rapidly after alloHSCT and gradually increased in the first two years post-transplant. However, patients with cGVHD had significantly fewer distinct Treg subpopulations, proposing a correlation between a disrupted Treg heterogeneity and cGVHD. Our study is the first to compare human Treg heterogeneity at birth, in healthy adults and in patients after alloHSCT with and without cGVHD. This approach to characterize Treg heterogeneity based on expression of a large panel of functional markers may enable future studies to identify specific Treg defects that contribute to immune dysfunction.

FOXO3a Activation by HDAC Class IIa Inhibition Induces Cell Cycle Arrest in Pancreatic Cancer Cells.

OBJECTIVES: Pancreatic cancer (PC) is highly aggressive with multiple oncogenic mutations. The efficacy of current chemotherapy is poor, and new therapeutic targets are needed. The forkhead box (FOX) proteins are multidirectional transcriptional factors strongly implicated in malignancies. Their expression is consistently suppressed by several oncogenic pathways such as PI3K/AKT signaling activated in PC. A recent study showed that class IIa histone deacetylases (HDAC) can act as a transcriptional suppressor. In this study, we hypothesized that HDAC class IIa inhibition would upregulate FOXO3a expression, thereby inducing its transcription-dependent antitumor effects. METHODS: We confirmed the change of FOXO3a expression and the effect of the cell growth inhibition by HDAC class IIa inhibition in AsPC-1 cells. Because FOXO3a is subject to ubiquitylation-mediated proteasome degradation, we examined the synergistic activation of FOXO3a by HDAC class IIa selective inhibitor TMP269 combined with proteasome inhibitor carfilzomib. RESULTS: We observed that TMP269 induced FOXO3a expression in a dose-dependent manner and inhibited cell growth in AsPC-1 cells. G1/S arrest was observed. FOXO3a expression was further increased and cell growth inhibition was dramatically enhanced by TMP269 combined with carfilzomib. CONCLUSIONS: Dual inhibition of class IIa HDACs and proteasome could be a promising new strategy for modifying FOXO3a activity against PC.

Management of Multiple Arteriovenous Malformations of the Small Bowel.

A 62-year-old Japanese female was referred to our hospital with gastrointestinal bleeding. Although small-bowel bleeding was suspected, no bleeding source was identified by enhanced computed tomography (CT), video capsule endoscopy (VCE), and double-balloon enteroscopy (DBE). Five years later, the patient had recurrent intermittent bloody stools with a significant decrease in hemoglobin levels. Although no active bleeding was observed on antegrade DBE, we detected a pulsatile submucosal uplift accompanied by a small red patch on the top of the uplift in the jejunum. Arteriovenous malformation (AVM) was suspected as the cause of small-bowel bleeding. Multiple-phase CT showed a number of small vascular ectasias during the arterial phase in the jejunum, and we confirmed the presence of multiple AVMs in the jejunum by selective angiography. To identify the location of the lesions and determine the minimal surgical margins, we performed intraoperative selective angiography with indocyanine green (ICG) injection. This technique allowed us to clearly observe the region and perform segmental small-bowel resection with minimal surgical margin. The patient reported that she has had no gastrointestinal bleeding at the two years follow-up visit.

Total buried bumper syndrome: A case study in transabdominal removal using a technique of endoscopic submucosal dissection.

Tube removal by endoscopic submucosal dissection using needle and insulation-tipped diathermic knives against buried bumper syndrome is a reliable, noninvasive and safe procedure.

A dose-escalation study of docetaxel, oxaliplatin, and S-1 (DOS) as a first-line therapy for patients with unresectable metastatic gastric cancer.

PURPOSE: The aim of this study was to determine the recommended dose (RD) for a docetaxel/oxaliplatin/S-1 (DOS) regimen in patients with unresectable gastric cancer and to preliminarily evaluate its efficacy. METHODS: Previously untreated patients with histologically proven unresectable metastatic gastric cancer were enrolled (n = 16). Docetaxel and oxaliplatin were administered intravenously on day 8 and S-1 was administered orally twice a day on days 1-14. Each cycle was repeated every 3 weeks. Dose-limiting toxicities (DLTs) were evaluated during the first treatment cycle. Three dose escalations of DOS were employed in this study: level 1 (50/100/80 mg/m2), level 2 (50/130/80 mg/m2), and level 3 (60/130/80 mg/m2). RESULTS: According to the 3 + 3 dose-escalating schedule, we determined that the RD and maximum tolerated dose for this regimen were level 1 and level 2, respectively. The DLTs were grade 3 diarrhea and febrile neutropenia. The overall response rate was 78% (7/9) for patients with measurable lesions and consisted of two complete responses and five partial responses. Five patients underwent conversion surgery. The median follow-up time was 19 months with median survival time and progression-free survival being 19.6 months and 7.6 months, respectively. CONCLUSIONS: The results from this study demonstrated the safety and tolerability of DOS in unresectable metastatic gastric cancer patients and revealed promising preliminary efficacy with a high conversion rate. A phase II trial of DOS regimen using the identified RD is ongoing.

Neoadjuvant chemotherapy with docetaxel, nedaplatin, and fluorouracil for resectable esophageal cancer: A phase II study.

Cisplatin plus 5-fluorouracil is regarded as standard neoadjuvant chemotherapy for esophageal squamous cell carcinoma (ESCC) in Japan, but the prognosis remains poor. We have previously described how definitive chemoradiotherapy with docetaxel, nedaplatin, and 5-fluorouracil (DNF) led to a very high response rate and promising survival times. We therefore undertook a phase II trial to evaluate the feasibility and efficacy of neoadjuvant DNF. The study included patients with clinical stage Ib-III ESCC. Chemotherapy consisted of i.v. docetaxel (30 mg/m2 ) and nedaplatin (50 mg/m2 ) on days 1 and 8, and a continuous infusion of 5-fluorouracil (400 mg/m2 /day) on days 1-5 and 8-12, every 3 weeks. After three courses of chemotherapy, esophagectomy was carried out. The primary end-point was the completion rate of the protocol treatment. Twenty-eight patients were enrolled (cStage Ib/II/III, 2/3/23) and all received at least two cycles of chemotherapy. Twenty-five patients underwent surgery, all of whom achieved an R0 resection, leading to a completion rate of 89.3%. The overall response rate was 87.0%. A pathological complete response was confirmed in eight (32.0%) cases. Grade 3/4 adverse events included leukopenia (32.1%), neutropenia (39.3%), febrile neutropenia (10.7%), thrombocytopenia (10.7%), and diarrhea (14.3%), but were manageable. Treatment-related deaths and major surgical complications did not occur. Estimated 2-year progression-free and overall survival rates were 70.4% and 77.2%, respectively. Thus, DNF therapy was well tolerated and deemed feasible, with a strong tumor response in a neoadjuvant setting for ESCC. This trial is registered with the University Hospital Medical Information Network (UMIN ID: 000014305).

Docetaxel, cisplatin and S-1 (DCS) combination chemotherapy for gastric cancer patients with peritoneal metastasis: a retrospective study.

PURPOSE: Peritoneal metastasis (PM) in advanced or recurrent gastric cancer (AGC) is the most frequent cause of death from this disease. However, current treatments remain unsatisfactory. We previously conducted studies of docetaxel, cisplatin and S-1 (DCS) combination chemotherapy for AGC. The aim of this study was to investigate the benefits and tolerability of DCS in PM patients. METHODS: Patients were divided into three groups: patients without PM (non-PM); PM patients without ascites, or mild to moderate ascites (None-Mod); and PM patients with massive ascites (Massive). Patients received oral S-1 (40 mg/m2 b.i.d.) on days 1-14, and intravenous cisplatin (60 mg/m2) and docetaxel (50-60 mg/m2) on day 8 every 3 weeks. Drug exposure, adverse events, tumor response, progression-free and overall survival (OS) rates were evaluated. RESULTS: Of the 111 AGC patients who received DCS as first-line therapy, 37 cases had complicated PM, 15 of whom displayed massive ascites. The response rate for PM patients was 81.5%. Drug exposure and toxicities were not meaningfully different among the groups. The MSTs were also similar: 22.6 months for the non-PM, 21.7 months for the None-Mod PM, and 16.8 months for the Massive, respectively. Ten (27.0%) patients with PM achieved downstaging and underwent curative surgery, subsequently demonstrating an excellent MST of 28.0 months. An independent prognostic factor for OS, as revealed by multivariate analyses. was a good performance status. CONCLUSION: DCS is feasible and efficacious for AGC with PM, especially when patients present with a good PS.

A triplet combination with capecitabine/oxaliplatin/irinotecan (XELOXIRI) plus cetuximab as first-line therapy for patients with metastatic colorectal cancer: a dose escalation study.

PURPOSE: The addition of cetuximab to triplet chemotherapy can increase treatment efficacy for patients with metastatic colorectal cancer (mCRC). We explored the dose-limiting toxicity and feasibility of a triweekly capecitabine, oxaliplatin, irinotecan, plus cetuximab (XELOXIRI plus cetuximab) regimen in patients with wild-type KRAS mCRC. METHODS: Patients received oxaliplatin (100 mg/m2, day 1), capecitabine (1700 mg/m2 per day from day 2 to 15), irinotecan (100, 120, and 150 mg/m2 for dose levels 1, 2, 3, respectively, on day 1), and cetuximab (400 mg/m2, day 1 and, thereafter, 250 mg/m2 every week), repeated every 3 weeks. Dose-limiting toxicities (DLTs) were assessed in the first 2 treatment cycles to determine the maximum tolerated dose (MTD) and the recommended dose (RD). RESULTS: Twelve patients received a median of 7 cycles of therapy (range 2-10). The DLT was grade 4 neutropenia, observed in 1 of 6 patients at dose level 2. The MTD was not reached at dose level 3. Therefore, the RD of irinotecan was defined as 150 mg/m2. Most common grade ≥ 3 toxicities were neutropenia (50%), diarrhea (17%), and febrile neutropenia (8%). The response rate was 83% (complete and partial response: 1 and 9 patient(s), respectively), including 4 conversion cases. CONCLUSIONS: The combination of XELOXIRI and cetuximab is feasible and has an acceptable toxicity profile; neutropenia was the DLT. The RD of irinotecan is 150 mg/m2. The observed response rate was promising and warrants further investigation.

A phase II study of modified docetaxel, cisplatin, and S-1 (mDCS) chemotherapy for unresectable advanced gastric cancer.

PURPOSE: Triplet therapy using docetaxel, cisplatin, and S-1 (DCS) against unresectable gastric cancer as previously reported by us showed high clinical efficacy, with a 87.1% total response rate; however, it also showed a high incidence of grade 3/4 toxicity. With the aim of reducing toxicities, we conducted a phase II study of modified DCS (mDCS), using a reduced dose of docetaxel, and evaluated the clinical efficacy and adverse events of this regimen. METHODS: Patients with unresectable gastric cancer received chemotherapy with S-1 (40 mg/m2 b.i.d) on days 1-14, and docetaxel (50 mg/m2) plus cisplatin (60 mg/m2) on day 8 every 3 weeks. The primary endpoint was the response rate (RR). Overall (OS) and progression-free survival (PFS), and toxicities were also evaluated. RESULTS: Forty-nine patients were enrolled from November 2011 to April 2014, and 43 were eligible. The overall RR was 79.1%, including two cases of a complete response (4.7%), and 32 cases of a partial response (74.4%). Nine cases had stable disease (20.9%) but none showed progressive disease. Of the 43 cases, 15 cases (34.9%) underwent curative conversion surgery. The median PFS was 350 days (95% CI 240-416 days) and median OS was 722 days (95% CI 411 days-not reached). Grade 3/4 neutropenia developed in 79.1%, and febrile neutropenia in 34.9%, of patients. Non-hematological grade 3/4 adverse events were anorexia (25.6%), nausea (4.7%), and diarrhea (9.3%). CONCLUSION: Modified DCS therapy showed high clinical efficacy sufficient enough to attempt conversion therapy against unresectable gastric cancer. Modified DCS showed fewer toxicities, but careful management of these is still essential.

Cases of primary malignant melanoma and melanocytosis of the esophagus observed by magnifying endoscopy: Application to differential diagnosis: case series.

RATIONALE: Primary malignant melanoma of the esophagus (PMME) is a rare disease with an extremely poor prognosis. In contrast, melanocytosis is a benign condition defined as melanocytic proliferation with melanin deposition. PMME is often accompanied by melanocytosis, but differentiating between them is difficult because of their similar appearance. PATIENT CONCERNS: Here, we reported 3 PMME cases, 2 with melanocytosis. DIAGNOSES: Magnifying endoscopy revealed characteristic non-uniform pigmented spots along deformed intrapapillary capillary loops (IPCLs) in PMME, while melanocytosis showed fine granule-like or linearly arranged spots and intact IPCLs. INTERVENTIONS: The patients underwent endoscopic or surgical resection of each lesion. OUTCOMES: Histologically, magnified images reflected melanocyte growth. For cases 1 and 2, the patients remained disease-free for 61 and 15 months after endoscopic resection, respectively. In case 3, liver metastases developed two months after surgery, and the patient died from liver failure after six months. LESSONS: This is the first report describing differences in magnified views of the 2 diseases, which aids a differential diagnosis.

Conversion therapy for inoperable advanced gastric cancer patients by docetaxel, cisplatin, and S-1 (DCS) chemotherapy: a multi-institutional retrospective study.

BACKGROUND: Conversion therapy is an option for unresectable metastatic gastric cancer when distant metastases are controlled by chemotherapy; however, the feasibility and efficacy remain unclear. This study aimed to assess the feasibility and efficacy of conversion therapy in patients with initially unresectable gastric cancer treated with docetaxel, cisplatin, and S-1 (DCS) chemotherapy by evaluating clinical outcomes. METHODS: One hundred unresectable metastatic gastric cancer patients, enrolled in three DCS chemotherapy clinical trials, were retrospectively evaluated. The patients received oral S-1 (40 mg/m2 b.i.d.) on days 1-14 and intravenous cisplatin (60 mg/m2) and docetaxel (50-60 mg/m2) on day 8 every 3 weeks. Conversion therapy was defined when the patients could undergo R0 resection post-DCS chemotherapy and were able to tolerate curative surgery. RESULTS: Conversion therapy was achieved in 33/100 patients, with no perioperative mortality. Twenty-eight of the 33 patients (84.8 %) achieved R0 resection, and 78.8 % were defined as histological chemotherapeutic responders. The median overall survival (OS) of patients who underwent conversion therapy was 47.8 months (95 % CI 28.0-88.5 months). Patients who underwent R0 resection had significantly longer OS than those who underwent R1 and R2 resections (P = 0.0002). Of the patients with primarily unresectable metastases, 10 % lived >5 years. Among patients who underwent conversion therapy, multivariate analysis showed that the pathological response was a significant independent predictor for OS. CONCLUSIONS: DCS safely induced a high conversion rate, with very high R0 and pathological response rates, and was associated with a good prognosis; these findings warrant further prospective investigations.

Low-dose IL-2 selectively activates subsets of CD4+ Tregs and NK cells.

CD4+ regulatory T cells (CD4Tregs) play a critical role in the maintenance of immune tolerance and prevention of chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation. IL-2 supports the proliferation and survival of CD4Tregs and previous studies have demonstrated that IL-2 induces selective expansion of CD4Tregs and improves clinical manifestations of chronic GVHD. However, mechanisms for selective activation of CD4Tregs and the effects of low-dose IL-2 on other immune cells are not well understood. Using mass cytometry, we demonstrate that low concentrations of IL-2 selectively induce STAT5 phosphorylation in Helios+ CD4Tregs and CD56brightCD16- NK cells in vitro. Preferential activation and expansion of Helios+ CD4Tregs and CD56brightCD16- NK cells was also demonstrated in patients with chronic GVHD receiving low-dose IL-2. With prolonged IL-2 treatment for 48 weeks, phenotypic changes were also observed in Helios- CD4Tregs. The effects of low-dose IL-2 therapy on conventional CD4+ T cells and CD8+ T cells were limited to increased expression of PD-1 on effector memory T cells. These studies reveal the selective effects of low-dose IL-2 therapy on Helios+ CD4Tregs and CD56bright NK cells that constitutively express high-affinity IL-2 receptors as well as the indirect effects of prolonged exposure to low concentrations of IL-2 in vivo.

Relationship Between Increased Fucosylation and Metastatic Potential in Colorectal Cancer.

BACKGROUND: Fucose is utilized for the modification of different molecules involved in blood group determination, immunological reactions, and signal transduction pathways. We have recently reported that enhanced activity of the fucosyltransferase 3 and/or 6 promoted TGF-ß-mediated epithelial mesenchymal transition and was associated with increased metastatic potential of colorectal cancer (CRC), suggesting that fucose is required by CRC cells. With this in mind, we examined requirement of L-fucose in CRC cells and developed fucose-bound nanoparticles as vehicles for delivery of anticancer drugs specific to CRC. METHODS: In this study, we first examined the expression of fucosylated proteins in 50 cases of CRC by immunochistochemical staining with biotinylated Aleuria aurantia lectin (AAL). Then we carried out an L-fucose uptake assay using three CRC cell lines. Finally, we developed fucose-bound nanoparticles as vehicles for the delivery of an anticancer drug, SN38, and examined tumor growth inhibition in mouse xenograft model (n = 6 mice per group). All statistical tests were two-sided. RESULTS: We found a statistically significant relationship between vascular invasion, clinical stage, and intensity score of AAL staining (P ≤ .02). L-fucose uptake assay revealed that L-fucose incorporation, as well as fucosylated protein release, was high in cells rich in fucosylated proteins. L-fucose-bound liposomes effectively delivered Cy5.5 into CRC cells. The excess of L-fucose decreased the efficiency of Cy5.5 uptake through L-fucose-bound liposomes, suggesting an L-fucose receptor dependency. Intravenously injected, L-fucose-bound liposomes carrying SN38 were successfully delivered to CRC cells, mediating efficient tumor growth inhibition (relative tumor growth ratio: no treatment group [NT], 8.29 ± 3.09; SN38-treated group [SN38], 3.53 ± 1.47; liposome-carrying, SN38-treated group [F0], 3.1 ± 1.39; L-fucose-bound, liposome-carrying, SN38-treated group [F50], 0.94 ± 0.89; F50 vs NT, P = .003; F50 vs SN38, P = .02, F50 vs F0, P = .04), as well as prolonging survival of mouse xenograft models (log-rank test, P < .001). CONCLUSIONS: Thus, fucose-bound liposomes carrying anticancer drugs provide a new strategy for the treatment of CRC patients.