Background and purpose:Microsatellite instability (MSI) status is commonly applied to predict the prognosis and chemosensitivity in stage Ⅱ and stage Ⅲ colorectal cancer patients. However, researches of its function on metastasis colorectal cancer are limited. This study investigated its value on prognosis and chemosensitivity in metastatic colorectal cancer (CRC) patients.Methods:We retrospectively investigated tumor tissues from metastasis CRC patients who were treated with oxaliplatin and 5-FU-based therapy regimens (FOLFOX and XELOX). Immunostaining of proteins of the mismatch repair genehMLH1,hMSH2,hMSH6 andhPMS2 was performed. Prognostic value and chemosensitivity in patients with MSI status were also determined.Results:Clinical features from 113 patients were analyzed. No cor-relation of overall survival (OS) and chemosensitivity with MSI status was found. We further investigated 79 patients with synchronous metastasis and palliatively tumor resection. Median progression free survival (PFS) from 22 MSI patients was significant longer than that in 57 MSS patients (19.9 monthsvs 7 months,P=0.005). No significant difference was seen in OS comparison (P=0.07). MSI status was also an independent prognostic factors of PFS by Cox multivariate analysis (MSS/MSI,HR=2.079,P=0.043). Moreover, in this group, MSI patients had improved disease control rate (59.1%vs 31.6%, P=0.025) in chemosensitivity analysis than MSS patients.Conclusion:A better PFS in MSI patients with synchronous metastasis and palliative tumor resection was found after treated with oxaliplatin and 5-FU-based therapy and a better chemosensitivity in MSI patients was also found.

N 6-methyladenosine (m 6A) modification can regulate gene expression by influencing RNA stability, nuclear transport, translation efficiency, alternative splicing and degradation. Current studies have shown that m 6A modification is associated with multiple biological behaviors of melanoma, such as proliferation, metastasis and resistance to immunotherapy, but specific mechanisms still need further study. This review summarizes the regulation of m 6A RNA methylation, and its related biological behaviors and mechanisms of action in melanoma.

OBJECTIVE To study protective effect and potential mechanism of Modified yupingfeng nasal spray （YPF+） on nasal mucosal injury in allergic rhinitis （AR） model rats. METHODS AR model was induced by ovalbumin （OVA） and randomly divided into model group， YPF+group （50 µg/side，twice a day）， positive control group （Mometasone furoate aqueous nasal spray， 50 µg/side，once a day）； the blank group was set up， with 10 rats in each group. Administration groups were given relevant medicine， and blank group and model group were given equivalent normal saline for consecutive 4 weeks. Thirty minutes after last medication， the behavioral scores of rats were recorded， and the pathological changes of their nasal mucosa tissue were observed. The level of reactive oxygen species （ROS） in nasal mucosa tissue was detected. The protein and mRNA expressions of nucleotide- binding oligomerization domain-like receptor protein 3 （NLRP3），caspase-1，gasdermin D （GSDMD） were detected； the contents of interleukin-1β （IL-1β） and IL-18 in serum were also determined. RESULTS Compared with blank group， in model group， the nasal mucosa tissue structure was disordered， inflammatory cells infiltrated seriously， and lamina propria vascular dilation was visible； its behavioral score and pathological score， the level of ROS， protein and mRNA expressions of NLRP3， caspase-1 and GSDMD， serum contents of IL-1β and IL-18 in nasal mucosa tissue were increased significantly （P＜0.05）. Compared with model group， the symptoms of nasal mucosal injury in rats of each drug group were improved to varying degrees， and the above indicators were significantly reduced （P＜0.05）. CONCLUSIONS YPF+ may improve nasal mucosal injury of rats， relieve AR symptoms such as sneezing， itchy nose， runny nose， the mechanism of which may be associated with reducing the production of ROS in nasal mucosa and downregulating NLRP3/caspase-1/ GSDMD pathway.