MiR-21-5p Modulates Cisplatin-Resistance of CD44+ Gastric Cancer Stem Cells Through Regulating the TGF-ß2/SMAD Signaling Pathway.

Background: Cisplatin (DDP) resistance in gastric cancer (GC) is likely to come from gastric cancer stem cells (GCSC). It is a new idea to study the mechanism of the DDP-resistance in GCSC from miRNA. Materials and Methods: CD44+ GCSCs and CD44- control cells were constructed based on the HGC27 gastric cancer cell line. DDP sensitivities in CD44+ and CD44- cells were detected via CCK-8 assay. The differential expression of miR-21-5p in these cell lines was detected by RT‒qPCR. The expression levels of downstream TGF-ß2, SMAD2 and SMAD3 were determined through RT‒PCR and Western blotting. A luciferase assay was used to detect the relationship between miR-21-5p and TGFB2, and the TCGA database, clinical data from our centre, and vivo experiment were used for validation. Finally, we knocked down miR-21-5p to detect changes in cisplatin resistance in GCSCs and to verify changes in the levels of downstream pathways in GCSCs. Results: CD44+ GCSCs induced cisplatin resistance compared with CD44- cells. miR-21-5p was highly expressed in GCSCs, and the TGF-ß2/SMAD pathway was also highly expressed. TGFB2 was proven to be a downstream target gene of miR-21-5p and had a positive relationship with it in phenotype. After knockdown of miR-21-5p, the TGF-ß2/SMAD pathway was also inhibited, and the resistance of GCSCs to cisplatin was specifically decreased. Conclusion: MiR-21-5p promotes cisplatin resistance in gastric cancer stem cells by regulating the TGF-ß2/SMAD signalling pathway.

Clinical outcome and prognostic factors of T4N0M0 colon cancer after R0 resection: A retrospective study.

BACKGROUND: Paradoxically, patients with T4N0M0 (stage II, no lymph node metastasis) colon cancer have a worse prognosis than those with T2N1-2M0 (stage III). However, no previous report has addressed this issue. AIM: To screen prognostic risk factors for T4N0M0 colon cancer and construct a prognostic nomogram model for these patients. METHODS: Two hundred patients with T4N0M0 colon cancer were treated at Tianjin Medical University General Hospital between January 2017 and December 2021, of which 112 patients were assigned to the training cohort, and the remaining 88 patients were assigned to the validation cohort. Differences between the training and validation groups were analyzed. The training cohort was subjected to multivariate analysis to select prognostic risk factors for T4N0M0 colon cancer, followed by the construction of a nomogram model. RESULTS: The 3-year overall survival (OS) rates were 86.2% and 74.4% for the training and validation cohorts, respectively. Enterostomy (P = 0.000), T stage (P = 0.001), right hemicolon (P = 0.025), irregular review (P = 0.040), and carbohydrate antigen 199 (CA199) (P = 0.011) were independent risk factors of OS in patients with T4N0M0 colon cancer. A nomogram model with good concordance and accuracy was constructed. CONCLUSION: Enterostomy, T stage, right hemicolon, irregular review, and CA199 were independent risk factors for OS in patients with T4N0M0 colon cancer. The nomogram model exhibited good agreement and accuracy.

Clinical value of regional lymph node sorting in gastric cancer.

BACKGROUND: Increasing evidence have shown that regional lymph node metastasis is a critical prognostic factor in gastric cancer (GC). In addition, lymph node dissection is a key factor in determining the appropriate treatment for GC. However, the association between the number of positive lymph nodes and area of lymph node metastasis in GC remains unclear. AIM: To investigate the clinical value of regional lymph node sorting after radical gastrectomy for GC. METHODS: This study included 661 patients with GC who underwent radical gastrectomy at Tianjin Medical University General Hospital between January 2012 and June 2020. The patients were divided into regional sorting and non-sorting groups. Clinicopathological data were collected and retrospectively reviewed to determine the differences in the total number of lymph nodes and number of positive lymph nodes between the groups. Independent sample t-tests were used for intergroup comparisons. Continuous variables that did not conform to a normal distribution were expressed as median (interquartile range), and the Mann-Whitney U test was used for inter-group comparisons. RESULTS: There were no significant differences between the groups in terms of the surgical method, tumor site, immersion depth, and degree of differentiation. The total number of lymph nodes was significantly higher in the regional sorting group (n = 324) than in the non-sorting group (n = 337) (32.5 vs 21.2, P < 0.001). There was no significant difference in the number of positive lymph nodes between the two groups. A total of 212 patients with GC had lymph node metastasis in the lymph node regional sorting group, including 89 (41.98%) cases in the first dissection station and 123 (58.02 %) cases in the second dissection station. Binary and multivariate logistic regression results showed that the number of positive lymph nodes (P < 0.001) was an independent risk factor for lymph node metastases at the second dissection station. CONCLUSION: Regional sorting of lymph nodes after radical gastrectomy may increase the number of detected lymph nodes, thereby improving the reliability and accuracy of lymph node staging in clinical practice.

CD40×HER2 bispecific antibody overcomes the CCL2-induced trastuzumab resistance in HER2-positive gastric cancer.

BACKGROUND: There was much hard work to study the trastuzumab resistance in HER2-positive gastric cancer (GC), but the information which would reveal this abstruse mechanism is little. In this study, we aimed to investigate the roles of tumor cell-derived CCL2 on trastuzumab resistance and overcome the resistance by treatment with the anti-CD40-scFv-linked anti-HER2 (CD40 ×HER2) bispecific antibody (bsAb). METHODS: We measured the levels of CCL2 expression in HER2-positive GC tissues, and revealed biological functions of tumor cell-derived CCL2 on tumor-associated macrophages (TAMs) and the trastuzumab resistance. Then, we developed CD40 ×HER2 bsAb, and examined the targeting roles on HER2 and CD40, to overcome the trastuzumab resistance without systemic toxicity. RESULTS: We found the level of CCL2 expression in HER2-postive GC was correlated with infiltration of TAMs, polarization status of infiltrated TAMs, trastuzumab resistance and survival outcomes of GC patients. On exposure to CCL2, TAMs decreased the M1-like phenotype, thereby eliciting the trastuzumab resistance. CCL2 activated the transcription of ZC3H12A, which increased K63-linked deubiquitination and K48-linked auto-ubiquitination of TRAF6/3 to inactivate NF-κB signaling in TAMs. CD40 ×HER2 bsAb, which targeted the CD40 to restore the ubiquitination level of TRAF6/3, increased the M1-like phenotypic transformation of TAMs, and overcame trastuzumab resistance without immune-related adversary effects (irAEs). CONCLUSIONS: We revealed a novel mechanism of trastuzumab resistance in HER2-positive GC via the CCL2-ZC3H12A-TRAF6/3 signaling axis, and presented a CD40 ×HER2 bsAb which showed great antitumor efficacy with few irAEs.

Primary extraskeletal osteosarcoma of sigmoid mesocolon: a case report and a review of the literature.

BACKGROUND: Extraskeletal osteosarcoma (ESOS) is a rare mesenchymal malignancy, which produces osteoid, bone, or chondroid material and is located in the soft tissue without attachment to skeletal bones and periosteum. One of the things that ESOS originated from mesentery is much rarer. CASE PRESENTATION: A 75-year female had a history of pain in the left lower abdomen for more than 4 months. Abdominal computerized tomography (CT) and magnetic resonance imaging revealed a large, irregular, and solid-cystic mass (largest diameter was 11.5 cm). The tumor was radically removed during an open operation. It was composed of abundant osteoid and polyhedral-shaped tumor cells with high atypia and high mitotic activity microscopically. The final pathological diagnosis was osteoblastic osteosarcoma, arising from the sigmoid mesocolon with negative margins. A 9-month follow-up by CT exhibited signs of peritoneal metastasis. CONCLUSIONS: Given the rarity of cases of mesenteric ESOS, diagnosis mainly depended on pathology findings or should be taken into consideration when the mesenteric mass was found. Its most effective treatment had not been determined, with surgical excision being generally accepted. Ensuring negative surgical margins may be an important factor affecting prognosis.