Analysis of clinical characteristics of mismatch repair status in colorectal cancer: a multicenter retrospective study.

BACKGROUND: Microsatellite instability (MSI) caused by DNA mismatch repair (MMR) deficiency is of great significance in the occurrence, diagnosis and treatment of colorectal cancer (CRC). AIM: This study aimed to analyze the relationship between mismatch repair status and clinical characteristics of CRC. METHODS: The histopathological results and clinical characteristics of 2029 patients who suffered from CRC and underwent surgery at two centers from 2018 to 2020 were determined. After screening the importance of clinical characteristics through machine learning algorithms, the patients were divided into deficient mismatch repair (dMMR) and proficient mismatch repair (pMMR) groups based on the immunohistochemistry results and the clinical feature data between the two groups were observed by statistical methods. RESULTS: The dMMR and pMMR groups had significant differences in histologic type, TNM stage, maximum tumor diameter, lymph node metastasis, differentiation grade, gross appearance, and vascular invasion. There were significant differences between the MLH1 groups in age, histologic type, TNM stage, lymph node metastasis, tumor location, and depth of invasion. The MSH2 groups were significantly different in age. The MSH6 groups had significant differences in age, histologic type, and TNM stage. There were significant differences between the PMS2 groups in lymph node metastasis and tumor location. CRC was dominated by MLH1 and PMS2 combined expression loss (41.77%). There was a positive correlation between MLH1 and MSH2 and between MSH6 and PMS2 as well. CONCLUSIONS: The proportion of mucinous adenocarcinoma, protruding type, and poor differentiation is relatively high in dMMR CRCs, but lymph node metastasis is rare. It is worth noting that the expression of MMR protein has different prognostic significance in different stages of CRC disease.

[Experimental study of repairing fat defect with human hair keratin material].

OBJECTIVE: To investigate the feasibility of adipogenesis from human hair keratin (HHK) material, so as to provide a new method for fat defect and depression deformity. METHODS: 3 Tibet mini-pigs were used. 8 fat defects (1.5 cm in diameter) were made bilaterally on the back. The ball-shaped HHK material was implanted to repair the defects at one side. The defects at contralateral side were as controls. The absorption of the HHK material and adipogenesis were studied histologically. RESULTS: 2 weeks after implantation, connective tissue and capillary grew into the porous HHK material. 4 weeks after implantation, HHK material was almost totally absorbed, leaving some material debris and foreign body granuloma. Around them, there were clusters of adipocyte. 6 weeks after implantation, the HHK material was totally degraded and the granuloma was disappeared, and then de novo adipose tissue was observed. Its volume was close to the volume of peripheral HHK material that was planted originally. 10 weeks later, the new-formed fat tissue had less fibres and was very similar to the normal fat. CONCLUSIONS: New adipose tissue can be formed after HKK material implantation. It can also be remodeled to be similar to normal fat.

[Use of high-risk human papillomavirus DNA testing to deal with atypical squamous cells undetermined significance and low squamous intraepithelial lesion].

OBJECTIVE: To explore the role of high-risk human papillomavirus (HPV) DNA testing in improvement of recognition of cervical intraepithelial lesions (CIN) 2, 3 or cervical cancer confirmed by biopsy in women with abnormal cervical cytology including atypical squamous cells undetermined significance (ASC-US) and low squamous intraepithelial lesion (LSIL). METHODS: Total 940 patients with abnormal cervical liquid-based cytology including ASC-US and LSIL were included in this study. Hybrid capture II assay was applied in the high-risk HPV detection. The cervical pathologic diagnoses were obtained under colposcopy guided biopsy. RESULTS: Of the 940 cases, 497 were ASC-US, and 443 LSIL. With pathological diagnosis of cervical biopsy, 417 cases were chronic inflammation, 315 condyloma, 124 CIN 1, 65 CIN 2, 19 CIN 3 or cervical cancer. The positive rate of high-risk HPV DNA in groups of ASC-US and LSIL were 59.6% and 84.9%, respectively. In each group of abnormal cytology, detection rates of CIN 2, 3 or cervical cancer in patients with positive HPV DNA were 8.8% and 14.1%, respectively, which were higher than those with negative HPV DNA (0.2% and 6.0%, P < 0.05). In group of ASC-US, high-risk HPV DNA test had a negative predictive value of 99.5%; detection rates of CIN 2, 3 or cervical cancer in patients with HPV DNA virus load 1-9.99 and > or = 10 was 1.6% and 10.7%, respectively. CONCLUSION: High-risk HPV DNA test were helpful to improve the detection rates of CIN 2, 3 or cervical cancer in patients with ASC-US.