A prospective cohort study of a new electrosurgical unit for preventing colorectal post-endoscopic submucosal dissection coagulation syndrome.

BACKGROUND AND AIM: Post-endoscopic submucosal dissection coagulation syndrome (PECS) is a recognized complication of colorectal endoscopic submucosal dissection (ESD); however, there is a lack of interventions for preventing PECS. We therefore conducted a prospective study to evaluate the utility of maXium, a novel electrosurgical unit, for preventing PECS. METHODS: This single-center, prospective cohort study prospectively enrolled patients undergoing colorectal ESD. The voltage and power of the electrosurgical units were measured. PECS was defined as a visual analog scale (VAS) ≥ 30 mm, an increase of VAS ≥ 20 mm from baseline, body temperature ≥ 37.5°C, or white blood cell count ≥ 10 000/µL after ESD. PECS was classified into type I (without extra-luminal air) and type II (with peri-luminal air). The primary endpoint was the incidence of PECS. A sample size of 92 patients was required to ensure the upper limit of the 90% CI for the incidence of PECS was less than 15%. RESULTS: At resistances greater than 400 Ω, the maXium unit allowed submucosal dissection with lower power than with the VIO300D unit. Ninety-one patients meeting the inclusion criteria were included in the final study analysis. The incidence of PECS was 16% (90% CI, 10-23%), comprising type I (11%) and type II (5%) PECS. Simple extra-luminal air without PECS was observed in 7% of patients. CONCLUSION: Use of the maXium electrosurgical unit did not reduce the incidence of PECS after colorectal ESD; however, the maXium unit had equivalent performance to a conventional electrosurgical unit used for colorectal ESD.

Clinical Impact of Proton Pump Inhibitor and Potassium-Competitive Acid Blocker for Predicting the Curability of Endoscopic Resection in Ulcerative Early Gastric Cancer.

INTRODUCTION: Endoscopic diagnosis is essential for predicting the curability of early gastric cancer (EGC; R0 resection) before treatment, but the relationship between ulcerative lesions and clinical outcomes remains unclear. We aimed to investigate the effect of proton pump inhibitor (PPI) or potassium-competitive acid blocker (P-CAB) on the morphological changes of ulcerative EGCs and its relevance to the clinical outcomes. METHODS: Altogether, 143 patients with differentiated ulcerative EGC that were resected by endoscopic submucosal dissection were retrospectively identified and divided into the following two cohorts depending on their PPI/P-CAB administration status: PPI/P-CAB (n = 76) and non-PPI/P-CAB (n = 67) cohorts. Furthermore, in each cohort, the patients were further divided into the improved and unimproved subgroups based on the ulcerative changes. RESULTS: In the PPI/P-CAB cohort, the deep submucosal invasion and lymphovascular invasion rates were significantly higher in the unimproved subgroup than in the improved subgroup, resulting in a significantly lower R0 resection rate. Contrarily, no significant differences were found between the two subgroups in the non-PPI/P-CAB cohort. The significance of PPI/P-CAB administration was observed only in the ulcerative EGCs with open-type atrophy (R0 resection rate; improved vs. unimproved, 90.9% vs. 48.0%, p = 0.001). When the finding of improved ulcer with PPI/P-CAB administration was used as the indication of endoscopic resection in ulcerative EGCs with open-type atrophy, high sensitivity (78.9%) and accuracy (76.3%) rates for the curability were observed, which were higher than those of conventional endoscopic diagnosis alone (p = 0.021). CONCLUSION: PPI or P-CAB administration might contribute to the potential selection of ulcerative EGCs, enabling endoscopic curative resection.

Krüppel-like Factor-4-Mediated Macrophage Polarization and Phenotypic Transitions Drive Intestinal Fibrosis in THP-1 Monocyte Models In Vitro.

Background and Objectives: Despite the fact that biologic drugs have transformed inflammatory bowel disease (IBD) treatment, addressing fibrosis-related strictures remains a research gap. This study explored the roles of cytokines, macrophages, and Krüppel-like factors (KLFs), specifically KLF4, in intestinal fibrosis, as well as the interplay of KLF4 with various gut components. Materials and Methods: This study examined macrophage subtypes, their KLF4 expression, and the effects of KLF4 knockdown on macrophage polarization and cytokine expression using THP-1 monocyte models. Co-culture experiments with stromal myofibroblasts and a conditioned medium from macrophage subtype cultures were conducted to study the role of these cells in intestinal fibrosis. Human-induced pluripotent stem cell-derived small intestinal organoids were used to confirm inflammatory and fibrotic responses in the human small intestinal epithelium. Results: Each macrophage subtype exhibited distinct phenotypes and KLF4 expression. Knockdown of KLF4 induced inflammatory cytokine expression in M0, M2a, and M2c cells. M2b exerted anti-fibrotic effects via interleukin (IL)-10. M0 and M2b cells showed a high migratory capacity toward activated stromal myofibroblasts. M0 cells interacting with activated stromal myofibroblasts transformed into inflammatory macrophages, thereby increasing pro-inflammatory cytokine expression. The expression of IL-36α, linked to fibrosis, was upregulated. Conclusions: This study elucidated the role of KLF4 in macrophage polarization and the intricate interactions between macrophages, stromal myofibroblasts, and cytokines in experimental in vitro models of intestinal fibrosis. The obtained results may suggest the mechanism of fibrosis formation in clinical IBD.

Metal-conjugated Maltotriose Chlorins as Novel Photosensitizers for Photodynamic Therapy.

BACKGROUND/AIM: Photodynamic therapy (PDT) is a relatively non-invasive anti-cancer therapy that employs a photosensitizer with a specific wavelength of light, causing a photochemical reaction that releases free radicals, thereby inducing tumor cell necrosis via oxidative stress. The oxygen molecule reaches the singlet excited state through efficient energy transfer from an excited triplet state of the photosensitizer. Heavy atoms are frequently introduced in photosensitizers for efficiently generating reactive oxygen species (ROS) in PDT, known as the heavy atom effect. However, metal-complexed photosensitizers often show low water-solubility. To overcome this limitation and produce ROS effectively, we focused on the better solubility of photosensitizers with heavy metals bound within the chlorin skeleton and conjugated with glucose in this study. MATERIALS AND METHODS: We established maltotriose (Mal3)-conjugation with heavy metallochlorins [M (Mal3-chlorin), M=Pt or Pd)] and evaluated its anti-tumor effect. RESULTS: M (Mal3-chlorin) showed effective ROS production and singlet oxygen induction. Consequently, these cytotoxic factors caused effective anti-tumor effects and induced morphological changes, followed by cell death in vitro. In a xenograft tumor mouse model, PDT with M (Mal3-chlorin) showed tumor growth suppression. CONCLUSION: M (Mal3-Chlorin) might be an excellent glucose-conjugated chlorin because of its strong anti-tumor PDT effect.

Urinary dipeptidase 1 and trefoil factor 1 are promising biomarkers for early diagnosis of colorectal cancer.

BACKGROUND: Currently utilized serum tumor markers and fecal immunochemical tests do not have sufficient diagnostic power for colorectal cancer (CRC) due to their low sensitivities. To establish non-invasive urinary protein biomarkers for early CRC diagnosis, we performed stepwise analyses employing urine samples from CRCs and healthy controls (HCs). METHODS: Among 474 urine samples, 363 age- and sex-matched participants (188 HCs, 175 stage 0-III CRCs) were randomly divided into discovery (16 HCs, 16 CRCs), training (110 HCs, 110 CRCs), and validation (62 HCs, 49 CRCs) cohorts. RESULTS: Of the 23 urinary protein candidates comprehensively identified from mass spectrometry in the discovery cohort, urinary levels of dipeptidase 1 (uDPEP1) and Trefoil factor1 (uTFF1) were the two most significant diagnostic biomarkers for CRC in both training and validation cohorts using enzyme-linked immunosorbent assays. A urinary biomarker panel comprising uDPEP1 and uTFF1 significantly distinguished CRCs from HCs, showing area under the curves of 0.825-0.956 for stage 0-III CRC and 0.792-0.852 for stage 0/I CRC. uDPEP1 and uTFF1 also significantly distinguished colorectal adenoma (CRA) patients from HCs, with uDPEP1 and uTFF1 increasing significantly in the order of HCs, CRA patients, and CRC patients. Moreover, expression levels of DPEP1 and TFF1 were also significantly higher in the serum and tumor tissues of CRC, compared to HCs and normal tissues, respectively. CONCLUSIONS: This study established a promising and non-invasive urinary protein biomarker panel, which enables the early detection of CRC with high sensitivity.

The promise and challenges of combination therapies with antibody-drug conjugates in solid tumors.

Antibody-drug conjugates (ADCs) represent an important class of cancer therapies that have revolutionized the treatment paradigm of solid tumors. To date, many ongoing studies of ADC combinations with a variety of anticancer drugs, encompassing chemotherapy, molecularly targeted agents, and immunotherapy, are being rigorously conducted in both preclinical studies and clinical trial settings. Nevertheless, combination therapy does not always guarantee a synergistic or additive effect and may entail overlapping toxicity risks. Therefore, understanding the current status and underlying mechanisms of ADC combination therapy is urgently required. This comprehensive review analyzes existing evidence concerning the additive or synergistic effect of ADCs with other classes of oncology medicines. Here, we discuss the biological mechanisms of different ADC combination therapy strategies, provide prominent examples, and assess their benefits and challenges. Finally, we discuss future opportunities for ADC combination therapy in clinical practice.

Spatiotemporal Quantification of HER2-targeting Antibody-Drug Conjugate Bystander Activity and Enhancement of Solid Tumor Penetration.

PURPOSE: Antibody-drug conjugate (ADC) has had a transformative effect on the treatment of many solid tumors, yet it remains unclear how ADCs exert bystander activity in the tumor microenvironment. EXPERIMENTAL DESIGN: Here, we directly visualized and spatiotemporally quantified the intratumor biodistribution and pharmacokinetics of different ADC components by developing dual-labeled fluorescent probes. RESULTS: Mechanistically, we found that tumor penetration of ADCs is distinctly affected by their ability to breach the binding site barrier (BSB) in perivascular regions of tumor vasculature, and bystander activity of ADC can only partially breach BSB. Furthermore, bystander activity of ADCs can work in synergy with coadministration of their parental antibodies, leading to fully bypassing BSBs and enhancing tumor penetration via a two-step process. CONCLUSIONS: These promising preclinical data allowed us to initiate a phase I/II clinical study of coadministration of RC48 and trastuzumab in patients with malignant stomach cancer to further evaluate this treatment strategy in humans.

Unanticipated pathological clearance in two cases of clinical T4b dMMR/MSI-h advanced colorectal cancer: the potential of immune checkpoint inhibitors despite positive positron-emission tomography results.

BACKGROUND: The standard treatment for colorectal cancer consists of surgery and chemotherapy, which can be combined to improve outcomes. Immune checkpoint inhibitors (ICI) are a significant advancement in the standard treatment of metastatic, unresectable colorectal cancer with deficient mismatch repair (dMMR). However, limited data are available about the use of ICI in the neoadjuvant and conversion settings. Here, we present two cases treated with ICI. CASE PRESENTATION: Case 1: A 75-year-old male with a large, borderline resectable rectal cancer diagnosed as cT4bN1bM0 who underwent neoadjuvant chemotherapy, followed by combination ICI consisting of ipilimumab and nivolumab. After four courses of ICI, the tumor significantly shrank, but positron emission tomography still showed a positive result and R0 resection was performed. Pathological analysis revealed no residual cancer cells. The patient has been monitored without adjuvant chemotherapy, and no recurrences have occurred after one year. Case 2: A 60-year-old male with locally advanced sigmoid colon cancer who received neoadjuvant treatment with pembrolizumab. The tumor partially shrank after three courses, and continued pembrolizumab monotherapy resulted in further tumor shrinkage which still showed positive positron emission tomography. Curative sigmoidectomy with partial resection of the ileum and bladder was performed, and the pathological outcome was pCR. There was no viable tumor in the specimen. The patient has been monitored without adjuvant chemotherapy for six months, and no recurrence has been observed. CONCLUSIONS: The present study reports two cases, including a large, borderline resectable rectal cancer after failure of chemotherapy followed by combination treatment with nivolumab and ipilimumab and one case of sigmoid colon cancer after pembrolizumab treatment, which resulted in pathological complete response. However, it remains unknown whether ICI therapy can replace surgery or diminish the optimal extent of resection, or whether adjuvant chemotherapy is needed after surgery in the case of achieving pCR after ICI therapy. Overall, this case report suggests that ICI before colorectal surgery can be effective and potentially a 'watch-and-wait" strategy could be used for cases in which ICI is effective.

Epigenetic Reprogramming Potentiates ICAM1 Antibody Drug Conjugates in Preclinical Models of Melanoma.

Therapeutic benefits and underlying biomechanism(s) of antibody drug conjugates (ADC) in combination with other targeted therapeutics are largely unknown. Here, the synergy between ADC and epigenetic drug decitabine (DAC), a clinically approved DNA methylation inhibitor, in multiple preclinical models of melanoma specifically investigated. Mechanistically, the underlying biomechanisms of how DAC cooperatively worked with ICAM1 antibody conjugated DNA topoisomerase I inhibitor DXd (I1-DXd) is elucidated. DAC treatment significantly enhanced anti-tumor efficacy of I1-DXd by upregulating antigen expression, enhancing antibody internalization and potentiating tumor sensitivity by epigenetically reprogramming of melanoma. Meanwhile, I1-DXd/DAC combination also exerted regulatory effects on tumor microenvironment (TME) by enhancing tumor infiltration of innate and adaptive immune cells and improving penetration of ADCs with a boosted antitumor immunity. This study provides a rational ADC combination strategy for solid tumor treatment.

BRAF K601E-mutated metastatic colorectal cancer in response to combination therapy with encorafenib, binimetinib, and cetuximab: A case report.

BACKGROUND: BRAF mutation has been recognized as a negative prognostic marker for metastatic colorectal cancer (mCRC), but these data are from common BRAF V600E-mutated mCRC. Combination therapy of BRAF inhibitor and anti-epidermal growth factor receptor (EGFR) antibody has been approved for BRAF V600E-mutated mCRC. However, BRAF non-V600 mutations are rare mutations, and their clinical behavior is not understood. Moreover, the BRAF K601E mutation is extremely rare in mCRC, and there have been no reports on its specific treatment. CASE SUMMARY: Herein, we report the case of a 59-year-old female with super aggressive mCRC with multiple metastases, which extended to whole body including mediastinal to abdominal lymph nodes, bones, pleura, and peritoneum. The companion diagnostics of tumor tissues showed RAS/BRAF wild-type without microsatellite instability. She received chemotherapy with mFOLFOX6 (oxaliplatin plus infusional 5-fluorouracil [5-FU] and leucovorin) plus panitumumab, following FOLFIRI (irinotecan plus infusional 5-FU and leucovorin) plus ramucirumab. For the next regimen selection, a comprehensive genomic profiling panel was performed and revealed a BRAF K601E mutation, which was not covered in the initial companion diagnostics. After disease progression, a combination of encorafenib, binimetinib, and cetuximab was selected as third-line chemotherapy. The serum levels of tumor markers were immediately decreased accompanied by improvements in pleural effusion and ascites. However, the disease progressed again, and best supportive care was done instead. CONCLUSION: This case offers novel insights into the clinical behaviors of BRAF non-V600E-mCRC, potentially advancing personalized therapy for rare and aggressive cases.

Real-world data on efficacy/safety and economic impact of nivolumab administered every 2 and 4 weeks among Japanese patients.

AIM: A new treatment interval for nivolumab administration at 480 mg every 4 weeks, in addition to 240 mg every 2 weeks, was approved in Japan in 2020. Using model-based evaluation, it was speculated that the effects or safety of nivolumab do not differ between the two treatment intervals; however, real-world data on nivolumab efficacy, safety, and economic impact are lacking. Accordingly, we aimed to examine the effects of nivolumab treatment intervals (2 weeks vs. 4 weeks) in terms of efficacy, safety, and economic impact in Japanese patients with cancer. METHODS: We retrospectively analyzed 126 patients treated with nivolumab. The patients were divided into two groups depending on whether they received nivolumab at 240 mg every 2 weeks (2-week group) or 480 mg every 4 weeks (4-week group). RESULTS: Efficacy results found no significant difference between the 4- and 2-week groups considering median overall survival (p = 0.70) and median progression-free survival (p = 0.57). The incidence of any grade and ≥  grade 3 immune-related adverse events did not differ between the 4-week and 2-week groups (any grade, p = 0.13; ≥  grade 3, p = 0.36). Excluding drug costs, the 4-week group had significantly lower medical costs than the 2-week group (2-week vs. 4-week: mean, 94,659 JPY [679.0 USD] vs. 58,737 JPY [421.3 USD]; p < 0.05). CONCLUSION: Collectively, our findings suggest that nivolumab 480 mg every 4 weeks may be more effective than nivolumab 240 mg every 2 weeks in terms of economic impact.