Anti-tuberculosis (TB) drugs, while being highly potent in vitro, require prolonged treatment to control Mycobacterium tuberculosis (Mtb) infections in vivo. We report here that mesenchymal stem cells (MSCs) shelter Mtb to help tolerate anti-TB drugs. MSCs readily take up Mtb and allow unabated mycobacterial growth despite having a functional innate pathway of phagosome maturation. Unlike macrophage-resident ones, MSC-resident Mtb tolerates anti-TB drugs remarkably well, a phenomenon requiring proteins ABCC1, ABCG2 and vacuolar-type H+ATPases. Additionally, the classic pro-inflammatory cytokines IFNγ and TNFα aid mycobacterial growth within MSCs. Mechanistically, evading drugs and inflammatory cytokines by MSC-resident Mtb is dependent on elevated PGE2 signaling, which we verify in vivo analyzing sorted CD45−Sca1+CD73+-MSCs from lungs of infected mice. Moreover, MSCs are observed in and around human tuberculosis granulomas, harboring Mtb bacilli. We therefore propose, targeting the unique immune-privileged niche, provided by MSCs to Mtb, can have a major impact on tuberculosis prevention and cure.
PURPOSE: Globally, colorectal cancer (CRC) ranks third in terms of incidence and second in terms of mortality. A relatively low burden of CRC has been reported from low- and middle-income countries (LMIC), and there is a paucity of publications related to CRC from LMIC. PATIENTS AND METHODS: A computerized comprehensive structured CRC clinical database was developed. All the patients with histopathologically proven CRC undergoing either curative and palliative multimodality management or surgical interventions between 2000 and 2019 were included in the study. A descriptive analysis of the demographic profile and clinical spectrum was performed. RESULTS: A total of 970 patients of CRC were treated between 2000 and 2019. Of these, 401 patients (41.3%) had colon cancer and 569 (58.7%) had rectal cancer. The male-to-female ratio was 1.79:1. The mean age at presentation was 47.7 years. A total of 337 (34.7%) patients qualified as young CRC (≤ 40 years of age at diagnosis). The commonest symptom among patients with colon cancer was abdominal pain; 55.6% of patients had a right-sided primary tumor as compared with 42.2% with left-sided tumors. The commonest symptom among patients with rectal cancer was bleeding per rectum. The predominant location of the tumor was in the lower rectum (58%). Majority of patients with CRC presented with locally advanced stage II and III disease. The most common histologic subtype encountered for both colon and rectal cancers was adenocarcinoma (84.8% and 81.2%, respectively). CONCLUSION: This study has revealed certain important findings related to CRC in LMIC including a higher burden of young colorectal cancer, a relatively higher proportion of rectal cancers in comparison with colon cancer, a high percentage of patients with low-rectal cancer, and advanced stage at presentation.
Five-minute delayed dual-energy CT had a high positive correlation with histologic fibrosis scores and showed good diagnostic performance in estimating liver fibrosis. Background Normalized iodine concentration (NIC) (ratio of iodine concentration of liver to that of aorta) of liver at delayed dual-energy CT (DECT) may reflect the amount of fibrosis based on the ...
Apart from the skin and choroid plexus, primary malignant melanoma is rare at the other sites and lacks organized documentation. Here, we have tried to enumerate the primary malignant melanomas at various atypical sites, supported by literature review. Seventeen cases were identified from our records of the past 5 years, which had detailed clinical work-up to exclude a possibility of a metastasis. A clear female predominance with involvement of the lower genitourinary tract was identified. In addition to three cases from the vagina, two cases each from the cervix, ovary and urethra, respectively, such cases were also identified in cerebral cortex (frontal and fronto-parietal area), rectum, nasal cavity, tongue, breast and tonsillar fossa. Although many were amelanotic, no specific histology was noted. In conclusion, malignant melanomas can arise in unconventional areas. Gross tumor appearance and the unavailability of an immunohistochemical panel, may result in their misdiagnosis as primary epithelial malignancies. A possible metastasis should always be ruled out.
Herein, for the first time, we report aberrant expression of membrane-associated RING-CH8 (MARCH8) in human esophageal squamous cell carcinoma. MARCH8 is a member of the recently discovered MARCH family of really interesting new genes (RING) E3 ligases. Though initial studies primarily focused on its immunomodulatory role, the newly discovered targets of this E3 ligase point towards its possible role in other biological processes such as embryogenesis and inhibition of apoptosis. However, its relevance in cancers is yet to be elucidated. We carried out quantitative real time PCR and immunohistochemistry to examine the levels of MARCH8 mRNA and protein in esophageal squamous cell carcinoma tissues. The role of MARCH8 in esophageal cancer cells was evaluated by cell proliferation, clonogenic and migration/invasion assays and flow cytometry with MARCH8 gene knockdown. Significantly increased expression of MARCH8 mRNA was found in esophageal squamous cell carcinoma as compared to distant matched non-malignant tissues (p = 0.024, AUC = 0.654). Immunohistochemical analysis revealed overexpression of MARCH8 protein in 86% of esophageal squamous cell carcinoma tissues (p < 0.001, AUC = 0.908). Interestingly, intense nuclear staining of MARCH8 protein was detected in cancer cells in addition to its cytoplasmic expression. Knockdown of MARCH8 resulted in decreased proliferation, migration, invasion and clonogenic potential of esophageal cancer cells. In addition to this, silencing of MARCH8 induced apoptosis in esophageal cancer cells which was measured by cell cycle distribution assay which showed increase in sub G0 and G2/M populations (cell death) and decrease in S-phase population. To further check the type of apoptosis induced by MARCH8 silencing, annexin assay was performed which showed significant increase in the number of cells in early apoptotic phase. Overall, increased expression of MARCH8 gene in preneoplastic and neoplastic esophageal tissues and its knockdown effect on cancer cell properties demonstrated herein points towards the potential role of this protein in esophageal tumorigenesis.
2 August 2018 in Journal of Gastroenterology and Hepatology