Background: This study aimed to evaluate the relationship between lateral lymph node yield (LLNY) and the ratio of lateral positive lymph nodes to lymph node yield (LPLR) from initial lateral neck dissection (LND) in patients with papillary thyroid carcinoma (PTC), as well as the risk of recurrence in patients undergoing LND reoperations. Methods: This retrospective cohort study enrolled patients with PTC who underwent revision LND between 1 January 2012, and 31 December 2021. The initial and revised clinical data were retrieved. Patient demographics, clinicopathological features, clinical records, and follow-up information were also reviewed. LLNY and LPLR were determined during the initial LND. Results: In total, 156 patients with PTC were included in this study, with a median follow-up of 36.5 months; 107 had recurrent lateral neck disease. The optimal LLNY and LPLR cutoff values for recurrent/persistent disease were 24.5 and 32.74%, respectively. The high-risk group (LLNY<25) had the lowest recurrence-free survival rate compared with to moderate-risk group (LLNY≥25, LPLR≥32.74%) and low-risk group (LLNY≥25, LPLR<32.74%) (P<0.001). The moderate-risk group had lower recurrence-free survival than the low-risk group. Multivariate analysis revealed that an LLNY less than 25 in the initial LND was an independent risk factor for recurrence/persistence of lateral neck (P<0.001). Conclusions: This study identified that LLNY and LPLR were associated with recurrence/persistence in PTC patients at the time of revision surgery was performed.

BackgroundOverexpression of STOML2 has been widely reported in a variety of cancer, yet few has detailed its function and regulatory mechanism. This study aims to reveal the clinicopathologic significance and oncologic function of STOML2 in colorectal cancer, explore its specific mechanism by means of yeast two-hybrid assay and bioinformatics.MethodsExpression level of STOML2 in normal colon and CRC tissue from biobank in Nanfang Hospital was detected by pathologic methods. The malignant proliferation of CRC induced by STOML2 was validated via gain-of-function and loss-of-function experiments, with novel techniques applied, such as organoid culture, orthotopic model and endoscopy monitoring. Yeast two-hybrid assay was conducted to screen interacting proteins of STOML2, followed by bioinformatics to predict biological process and signaling pathway of candidate proteins. Target protein with most functional similarity to STOML2 was validated with co-immunoprecipitation, and immunofluorescence were conducted to co-localize STOML2 and PHB. Pathway regulated by STOML2 was detected with immunoblotting, and subsequent experimental therapy was conducted with RAF inhibitor Sorafenib.ResultsSTOML2 was significantly overexpressed in colorectal cancer and its elevation was associated with unfavorable prognosis. Knockdown of STOML2 suppressed proliferation of colorectal cancer, thus attenuated subcutaneous and orthotopic tumor growth, while overexpressed STOML2 promoted proliferation in cell lines and organoids. A list of 13 interacting proteins was screened out by yeast two-hybrid assay. DTYMK and PHB were identified to be most similar to STOML2 according to bioinformatics in terms of biological process and signaling pathways; however, co-immunoprecipitation confirmed interaction between STOML2 and PHB, rather than DTYMK, despite its highest rank in previous analysis. Co-localization between STOML2 and PHB was confirmed in cell lines and tissue level. Furthermore, knockdown of STOML2 downregulated phosphorylation of RAF1, MEK1/2, ERK1/2 and ELK1 on the MAPK signaling pathway, indicating common pathway activated by STOML2 and PHB in colorectal cancer proliferation.ConclusionsThis study demonstrated that in colorectal cancer, STOML2 expression is elevated and interacts with PHB through activating MAPK signaling pathway, to promote proliferation both in vitro and in vivo. In addition, combination of screening assay and bioinformatics marks great significance in methodology to explore regulatory mechanism of protein of interest.

BackgroundHighly expressed STOML2 has been reported in a variety of cancers, yet few have detailed its function and regulatory mechanism. This research aims to reveal regulatory mechanism of STOML2 and to provide evidence for clinical therapeutics, via exploration of its role in colorectal cancer, and identification of its interacting protein. MethodsExpression level of STOML2 in normal colon and CRC tissue from biobank in Nanfang Hospital was detected by pathologic methods. The malignant proliferation of CRC induced by STOML2 was validated via gain-of-function and loss-of-function experiments, with novel techniques applied, such as organoid culture, orthotopic model and endoscopy monitoring. Yeast two-hybrid assay screened interacting proteins of STOML2, followed by bioinformatics analysis to predict biological function and signaling pathway of candidate proteins. Target protein with most functional similarity to STOML2 was validated with co-immunoprecipitation, and immunofluorescence were conducted to co-localize STOML2 and PHB. Pathway regulated by STOML2 was detected with immunoblotting, and subsequent experimental therapy was conducted with RAF inhibitor Sorafenib.ResultsSTOML2 was significantly overexpressed in colorectal cancer and its elevation was associated with unfavorable prognosis. Knockdown of STOML2 suppressed proliferation of colorectal cancer, thus attenuated subcutaneous and orthotopic tumor growth, while overexpressed STOML2 promoted proliferation in cell lines and organoids. A list of 13 interacting proteins was screened out by yeast two-hybrid assay. DTYMK and PHB were identified to be most similar to STOML2 according to bioinformatics in terms of biological process and signaling pathways; however, co-immunoprecipitation confirmed interaction between STOML2 and PHB, rather than DTYMK, despite its highest rank in previous analysis. Co-localization between STOML2 and PHB was confirmed in cell lines and tissue level. Furthermore, knockdown of STOML2 downregulated phosphorylation of RAF1, MEK1/2, ERK1/2 and ELK1 on the MAPK signaling pathway, indicating common pathway activated by STOML2 and PHB in colorectal cancer proliferation.ConclusionsThis study demonstrated that in colorectal cancer, STOML2 expression is elevated and interacts with PHB through activating MAPK signaling pathway, to promote proliferation both in vitro and in vivo. In addition, combination of screening assay and bioinformatics marks great significance in methodology to explore regulatory mechanism of protein of interest.