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Acetylation, a critical regulator of diverse cellular processes, holds significant implications in various cancer contexts. Further understanding of the acetylation patterns of key cancer-driven proteins is crucial for advancing therapeutic strategies in cancer treatment. This study aimed to unravel the acetylation patterns of Engulfment and Cell Motility Protein 1 (ELMO1) and its relevance to the pathogenesis of colorectal cancer (CRC). Immunoprecipitation and mass spectrometry precisely identified lysine residue 505 (K505) as a central acetylation site in ELMO1. P300 emerged as the acetyltransferase for ELMO1 K505 acetylation, while SIRT2 was recognized as the deacetylase. Although K505 acetylation minimally affected ELMO1's localization and stability, it played a crucial role in mediating ELMO1-Dock180 interaction, thereby influencing Rac1 activation. Functionally, ELMO1 K505 acetylation proved to be a pivotal factor in CRC progression, exerting its influence on key cellular processes. Clinical analysis of CRC samples unveiled elevated ELMO1 acetylation in primary tumors, indicating a potential association with CRC pathologies. This work provides insights into ELMO1 acetylation and its significance in advancing potentially therapeutic interventions in CRC treatment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objectives: Emerging evidence has demonstrated that tumour budding (TB) is negatively associated with T-lymphocyte infiltration in CRC. Despite extensive research, the molecular characteristics of immunologically 'hot' TB remain poorly understood., Methods: We quantified the number of TB by haematoxylin-eosin (H&E) sections and the densities of CD3 + and CD8 + T-lymphocytes by immunohistochemistry in a CRC cohort of 351 cases who underwent curative resection. We analysed the differential expression and T-lymphocyte infiltration score of 37 human epithelial keratins in CRC using RNA sequencing from the TCGA dataset. In 278 TB-positive cases, KRT17 expression was evaluated in tumour centre (TC) and TB with a staining score. Patient demographic, clinicopathological features and survival rates were analysed., Results: In a CRC cohort of 351 cases, low-grade TB was associated with high CD3 + and CD8 + T-cell densities in the invasive margin (IM) but not in the TC. Of 37 human epithelial keratins, only KRT17 expression in TB had an apparent association with TB-grade and T-lymphocyte infiltration. In 278 TB-positive cases, high KRT17 expression in TB (KRT17TB) was negatively associated with low-grade TB and positively associated with high CD3 + and CD8 + T-cell densities in IM. High KRT17TB predicted early tumour grade, absence of lymph node metastasis and absence of tumour deposits. Additionally, patients with high KRT17TB had good overall survival and disease-free survival. Notably, low KRT17TB can specifically identify those patients with a poor prognosis among colorectal cancer patients with low TB and high T-lymphocyte infiltration., Conclusions: KRT17 can be employed as a new indicator for distinguishing different immunological TBs., Competing Interests: The authors declare no conflict of interest., (© 2024 The Authors. Clinical & Translational Immunology published by John Wiley & Sons Australia, Ltd on behalf of Australian and New Zealand Society for Immunology, Inc.)

Poor infiltration of T lymphocytes has been regarded as a crucial mechanism of tumor immune escape. Here, we demonstrate a protective role of KRT17 in colorectal cancer, where KRT17 reversed the tumor immunosuppressive microenvironment by increasing T-lymphocyte infiltration. High-throughput RNA sequencing suggested that KRT17 was significantly upregulated in deficient mismatch repair (dMMR) tumors compared with proficient mismatch repair (pMMR) tumors. In a colorectal cancer cohort of 446 cases, KRT17 expression positively correlated with better clinical outcomes. Krt17 overexpression decreased xenograft tumor growth in immune-competent mice. T-cell depletion in a murine model showed that the presence of T lymphocytes was necessary for Krt17-mediated disruption of tumorigenesis. Mass spectrometry and coimmunoprecipitation assays suggested KRT17 caused YTHDF2 degradation through the ubiquitin-proteasome system. Through high-throughput RNA immunoprecipitation sequencing, we found that CXCL10 was the target gene of the N6-methyladenosine (m6A) "reader" YTHDF2. KRT17 synergized with anti-PD-1 for better tumor control in an immunotherapy-resistant murine model. In a cohort of patients with colorectal cancer receiving pembrolizumab, high KRT17 expression was found within the tumors of responders. Collectively, we elucidated a critical role of KRT17 in colorectal cancer to prevent immune escape. These findings present new insights into potential therapeutic strategies and effective markers of immunotherapy reactivity against pMMR tumors., (©2023 The Authors; Published by the American Association for Cancer Research.)

Functional reprogramming of tumor-associated macrophages (TAMs) is crucial to their potent tumor-supportive capacity. However, the molecular mechanism behind the reprogramming process remains poorly understood. Here, we identify engulfment and cell motility protein 1 (ELMO1) as a crucial player for TAM reprogramming in colorectal cancer (CRC). The expression of ELMO1 in stromal but not epithelial tumor cells was positively associated with advanced clinical stage and poor disease-free survival in CRC. An increase in ELMO1 expression was specifically found in TAMs, but not in other multiple nonmalignant stromal cells. Gain- and loss-of-function assays indicated ELMO1 reprogrammed macrophages to a TAM-like phenotype through Rac1 activation. In turn, ELMO1-reprogrammed macrophages were shown to not only facilitate the malignant behaviors of CRC cells but exhibited potent phagocytosis of tumor cells. Taken together, our work underscores the importance of ELMO1 in determining functional reprogramming of TAMs and could provide new insights on potential therapeutic strategies against CRC., (© 2022 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

Introduction: Since transanal total mesorectal excision (taTME) was introduced, it has become an important topic in rectal cancer treatment. Many previous studies reported positive relevant short-term results, histopathological results, and associated complications. Recently, concerns regarding the oncological safety of taTME have been raised due to reports showing high local recurrences (LR) rates. Therefore, this study aimed to compare the 3-year outcomes between taTME and laparoscopic total mesorectal excision (laTME) for mid-low rectal cancer., Methods: A total of 104 patients who underwent taTME were matched with 208 patients treated by laTME. The primary endpoint was 3-year LR rate; secondary endpoints in this matched-cohort study included the perioperative outcomes and histopathological outcomes., Results: taTME was associated with lower permanent ostomy rate (1% vs 13.5%) and lower conversion rate (0% vs 3.4%) compared to laTME. A similar quality of resected specimens was detected for each group. In both groups, the local recurrence rate was 3.8%. Within 3 years after surgery, the disease-free survival (DFS) rates were 78.8% in the taTME group and 76.9% in the laTME group (P = 0.640), while the overall survival (OS) rates were 93.3% in the taTME group and 89.9% in the laTME group (P = 0.327)., Conclusion: No significant differences regarding 3-year local recurrence rate (3.8%) were observed in the taTME group compared to laTME group., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Inactive von Hippel-Lindau (VHL) is linked to metabolic reprogramming and plays pivotal roles in the pathogenesis of clear cell renal cell carcinoma (ccRCC). Here, we identify a previously unknown oncogenic role for inactive VHL in actively triggering histone lactylation to promote ccRCC progression. In patients with ccRCC, inactive VHL positively correlates with the presence of histone lactylation, and high levels of histone lactylation indicates poor patient prognosis. Inactive VHL-triggered histone lactylation contributes to ccRCC progression by activating the transcription of platelet-derived growth factor receptor β (PDGFRβ). In turn, PDGFRβ signaling is shown to stimulate histone lactylation, thereby forming an oncogenic positive feedback loop in ccRCC. Target correction of aberrant histone lactylation represses the growth and metastasis of ccRCC in vivo. More importantly, the combined inhibition of histone lactylation and PDGFRβ significantly reinforces the therapeutic efficacy. This work underscores the importance of histone lactylation in facilitating ccRCC progression and suggests targeting the positive feedback loop between histone lactylation and PDGFRβ signaling might provide a promising therapeutic strategy for ccRCC patients., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Background: Since Sylla and Lacy successfully reported the transanal total mesorectal excision in 2010, taTME was considered to have the potential to overcome some problematic laparoscopic cases in male, low advanced rectal cancer. However, the evidence is still lacking. This study compared the short and long outcomes of taTME with laTME in these "challenging" patients to explore the advantages of taTME among the patients., Method: After propensity score matching analysis, 106 patients were included in each group from 325 patients who met the including standard. Statistical analysis was used to compare the differences of perioperative outcomes, histopathological results, and survival results between taTME and laTME groups., Results: The mean time of pelvic operation in the taTME group was significantly shorter than in the laTME group (62.2 ± 14.2 mins vs 81.1 ± 18.9 mins, P = 0.003). The complication incidence rate and the rate of protective loop ileostomy in the taTME group were significantly lower than those in the laTME group (19.8% vs 38.7%, P = 0.003 and 70.8% vs 92.5%, P < 0.001). In long-term result, there was no significant difference between the two groups for 3-year OS (87.3% vs 85.4%, P = 0.86) or 3-year DFS (74.9% vs 70.1%, P = 0.92). The 2-year cumulative local recurrence rate was similar between the two groups (1.1% vs 5.8%, P = 0.22)., Conclusion: This study demonstrated that taTME might reduce the incidence of postoperative complications, especially of anastomotic leakage in these "challenging" patients. taTME may be considered to have clear advantages for "challenging" patients., Competing Interests: The authors declare that they have no conflicts of interest., (Copyright © 2022 Ze Li et al.)

Background: Ever since transanal total mesorectal excision was introduced by Sylla and Lacy in 2010, it has become more popular among colorectal surgeons. However, some surgeons hesitate to use it, because this novel approach differs greatly from laparoscopic total mesorectal excision and requires a long learning curve., Objective: This study analyzed the learning curve of transanal total mesorectal excision procedure and compared the different phases of transanal total mesorectal excision with laparoscopic total mesorectal excision., Design: This is retrospective case-control study., Settings: We used data from the approved colorectal cancer database of the Sixth Affiliated Hospital of Sun Yat-sen University., Patients: The patients involved in this study underwent transanal total mesorectal excision performed by a single surgeon (L.K.) or underwent laparoscopic transanal total mesorectal excision performed by experienced surgeons., Interventions: Transanal or laparoscopic resection of mid-low rectal cancer was conducted., Main Outcomes Measures: Perioperative complication and resection margin were measured., Results: A total of 342 patients were included in both groups. The learning curve of transanal total mesorectal excision was divided into 3 phases. Data show that demographics and tumor characteristics were not significantly different between the matched groups. Indeed, during phase 1, only operative time was longer than in the laparoscopic group, whereas, during phase 2, results from the transanal group were comparable with the laparoscopic group. Results show that, during phase 3, operative time, intraoperative blood loss, and postoperative hospital stay were all lower than in the laparoscopic group. Local recurrence occurred in 3 patients during phase 1 and in 1 patient during phase 2., Limitations: This study was a small retrospective study and focused on just 1 surgeon performing transanal total mesorectal excision., Conclusions: Short-term and histopathologic outcomes are similar compared between a transanal group and matched laparoscopic group. Transanal total mesorectal excision also provided good oncologic outcomes. See Video Abstract at http://links.lww.com/DCR/B450., Escisin Mesorrectal Total Transanal En El Cncer De Recto Mediobajo Evaluacin De La Curva De Aprendizaje Y Comparacin De Resultados a Corto Plazo Con Tme Laparoscpica Estndar: ANTECEDENTES:Desde que Sylla y Lacy introdujeron la escisión mesorrectal total transanal en 2010, se ha vuelto más popular entre los cirujanos colorrectales. Sin embargo, algunos cirujanos dudan en utilizarlo, porque este nuevo método difiere mucho de la escisión mesorrectal total laparoscópica y requiere una larga curva de aprendizaje.OBJETIVO:Este estudio analizó la curva de aprendizaje del procedimiento de escisión mesorrectal total transanal y comparó las diferentes fases de la escisión mesorrectal total transanal con la escisión mesorrectal total laparoscópica.DISEÑO:Este es un estudio retrospectivo de casos y controles.ENTORNO CLINICO:Utilizamos base de datos de cáncer colorrectal aprobada del Sexto Hospital Afiliado de la Universidad Sun Yat-sen (Guangzhou, China).PACIENTES:Los pacientes involucrados en este estudio fueron sometidos a escisión mesorrectal total transanal realizada por un solo cirujano (LK) o se sometieron a escisión mesorrectal total transanal laparoscópica realizada por cirujanos experimentados.INTERVENCIONES:Resección transanal o laparoscópica de cáncer de recto medio-bajo.PRINCIPALES MEDIDAS DE VOLARCION:complicación perioperatoria y margen de resección.RESULTADOS:Se incluyó un total de 342 pacientes en ambos grupos. La curva de aprendizaje de la escisión mesorrectal total transanal se dividió en tres fases. Los datos muestran que las características demográficas y tumorales no fueron significativamente diferentes entre los grupos emparejados. De hecho, durante la fase 1, solo el tiempo operatorio fue más largo que en el grupo laparoscópico. Mientras que durante la fase 2, los resultados del grupo transanal fueron comparables a los del grupo laparoscópico. Los resultados muestran que durante la fase 3, el tiempo operatorio, la pérdida de sangre intraoperatoria y la estancia hospitalaria postoperatoria fueron menores que en el grupo laparoscópico. La recurrencia local ocurrió en 3 pacientes durante la fase 1 y en 1 paciente durante la fase 2.LIMITACIONES:Este estudio fue un estudio retrospectivo pequeño y se centró en un solo cirujano que realizaba la escisión mesorrectal total transanal.CONCLUSIÓN:Los resultados a corto plazo e histopatológicos son similares en comparación entre el grupo transanal y el grupo laparoscópico emparejado. La escisión mesorrectal total transanal también proporcionó buenos resultados oncológicos. Consulte Video Resumen en http://links.lww.com/DCR/B450., Competing Interests: Financial Disclosure: The authors declare that they have no conflict of interest., (Copyright © The ASCRS 2021.)