Deletion and down-regulation of SMAD4 gene in colorectal cancers in a Chinese population

Objective： Colorectal cancer（CRC） is one of the most common types of human cancers. As a tumor suppressor, SMAD4 plays a key role in colorectal carcinogenesis and invasiveness. Copy number variations（CNVs） of the SMAD4 gene have been reported to be associated with cancer pathogenesis in array-based studies in different populations. Here we aimed to investigate the CNVs of the SMAD4 gene in a relatively large number of CRC patients from China. Methods： In the present study, we collected 147 Chinese CRC tumors as well as self-paired normal control tissues. Quantitative PCR was carried out to examine the copy number as well as the m RNA expression of the SMAD4 gene. Results： Our results showed that the copy number deletions of SMAD4 were frequent in a relatively high percentage of CRC samples（34.7%, 51 out of 147）. There was a positive correlation between the copy number decrease of SMAD4 and tumor progression in CRCs. Furthermore, copy number loss of SMAD4 was correlated with decreased m RNA expression.Conclusions： These findings suggested that the copy number deletions of SMAD4 were frequent in CRC patients from China and had the potential to serve as a diagnostic indicator, alone or in combination with other markers, for CRC.

SARS-CoV-2 Nsp8 induces mitophagy by damaging mitochondria

Autophagy plays an important role in the interaction between viruses and host cells.SARS-CoV-2 infection can disrupt the autophagy process in target cells.However,the precise molecular mechanism is still unknown.In this study,we discovered that the Nsp8 of SARS-CoV-2 could cause an increasing accumulation of autophagosomes by preventing the fusion of autophagosomes and lysosomes.From further investigation,we found that Nsp8 was present on mitochondria and can damage mitochondria to initiate mitophagy.The results of experiments with immunofluorescence revealed that Nsp8 induced incomplete mitophagy.Moreover,both domains of Nsp8 orchestrated their function during Nsp8-induced mitophagy,in which the N-terminal domain colocalized with mitochondria and the C-terminal domain induced auto/mitophagy.This novel finding expands our understanding of the function of Nsp8 in promoting mitochondrial damage and inducing incomplete mitophagy,which helps us to understand the etiology of COVID-19 as well as open up new pathways for creating SARS-CoV-2 treatment methods.

热疗联合放化疗治疗乳腺癌皮肤复发病例2例临床病理观察

背景:热疗目前广泛应用于辅助传统的放化疗手段治疗某些恶性肿瘤,尤其是对一些单纯依靠放化疗不敏感的肿瘤患者。辅助的热疗常可提高肿瘤病人对传统放化疗的敏感性。病例报告:我们报告两例乳腺癌根治术后复发患者,于腋窝部位皮下浅表软组织内发现转移灶,单纯应用放化疗治疗复发转移病灶效果不明显。随后,我们联合应用放化疗辅助热疗手段,转移瘤灶显著缩小,病理学活检提示肿瘤细胞坏死明显。患者生活质量得到改善。结论:热疗可以有效地提高某些肿瘤患者传统放化疗的敏感性,为某些对放化疗不敏感的肿瘤患者提供新的治疗途径。

Intratumoural microbiota:a new frontier in cancer development and therapy

Human microorganisms,including bacteria,fungi,and viruses,play key roles in several physiological and pathological processes.Some studies discovered that tumour tissues once considered sterile actually host a variety of microorganisms,which have been confirmed to be closely related to oncogenesis.The concept of intratumoural microbiota was subsequently proposed.Microbiota could colonise tumour tissues through mucosal destruction,adjacent tissue migration,and hematogenic invasion and affect the biological behaviour of tumours as an important part of the tumour microenvironment.Mechanistic studies have demonstrated that intratumoural microbiota potentially promote the initiation and progression of tumours by inducing genomic instability and mutations,affecting epigenetic modifications,promoting inflammation response,avoiding immune destruction,regulating metabolism,and activating invasion and metastasis.Since more comprehensive and profound insights about intratumoral microbiota are continuously emerging,new methods for the early diagnosis and prognostic assessment of cancer patients have been under examination.In addition,interventions based on intratumoural microbiota show great potential to open a new chapter in antitumour therapy,especially immunotherapy,although there are some inevitable challenges.Here,we aim to provide an extensive review of the concept,development history,potential sources,heterogeneity,and carcinogenic mechanisms of intratumoural microorganisms,explore the potential role of microorganisms in tumour prognosis,and discuss current antitumour treatment regimens that target intratumoural microorganisms and the research prospects and limitations in this field.

Implementing Routine HIV Screening in Hospitals:An Effective Practice to Expand HIV Testing—Xishuangbanna Prefecture,Yunnan Province,China,2019–2020

Summary What is already known about this topic?Research evidence is insufficient to suggest whether routine human immunodeficiency virus(HIV)screening in healthcare settings is effective in promoting greater awareness of HIV-positive status.What is added by this report?This study found that,following the implementation of routine HIV screening in hospitals in Xishuangbanna Prefecture,Yunnan Province,there was a significant increase in the number of HIV screenings,positive results,and the positive rate of HIV screening in primary-level hospitals.What are the implications for public health practice?Routine hospital-based HIV screening is effective in identifying HIV infections in areas with concentrated epidemics.