The impact of recent chemotherapy on immunity in 2 COVID-19 cases with gastrointestinal tumors: A case report.

INTRODUCTION: Coronavirus disease 2019 (COVID-19) is a rapidly emerging infectious respiratory disease caused by severe acute respiratory syndrome coronavirus 2. Currently, more than 100 million cases of COVID-19 have been confirmed worldwide, with over 2.4 million mortalities. The pandemic affects people of all ages but older individuals and those with severe chronic illnesses, including cancer patients, are at higher risk. PATIENT CONCERNS: The impact of cancer treatment on the progression of COVID-19 is unclear. Therefore, we assessed the effects of chemotherapy on COVID-19 outcomes for 2 cancer patients. On January 24, 2020, a level I response to a major public health emergency was initiated in Hubei Province, China, which includes Enshi Autonomous Prefecture that has a population of 4.026 million people. As of April 30, 2020, 252 confirmed cases of COVID-19 and 11 asymptomatic carriers were identified in Enshi. DIAGNOSIS: Among the confirmed cases and asymptomatic carriers, 2 patients were identified who were previously diagnosed with malignant tumors, including one with hepatocellular carcinoma and the other with cardia carcinoma. INTERVENTIONS: These 2 patients were receiving or just completed chemotherapy at the time of their COVID-19 diagnosis. OUTCOMES: Both patients were followed and presented favorable outcomes. The positive outcomes for these 2 patients could be partially explained by their recent chemotherapy that impacted their immune status. Also, their relatively younger ages and lack of comorbidities were likely factors in their successful recovery from COVID-19. CONCLUSIONS: Anticancer treatment might enhance a patient's ability to respond favorably to COVID-19 infection. However, anticancer treatment is likely to impact immune function differently in different individuals, which can influence disease outcomes.

[Effect of methyl eugenol on hypoxia/reoxygenation injury of human renal tubular epithelial cells and its mechanism].

This study aimed to investigate the effect of methyl eugenol(ME) on hypoxia/reoxygenation(H/R)-induced injury of human renal tubular epithelial HK-2 cells and its mechanism. The viability of HK-2 cells cultured with different concentrations of ME and exposed to H/R was detected by cell counting kit-8(CCK-8) assay. The effect of ME on the morphology of HK-2 cells was observed under an inverted microscope. The content of intracellular reactive oxygen species in different groups was detected after 2',7'-dichlorodihydrofluorescein diacetate(DCFH-DA) fluorescence staining. Cell apoptosis was determined by flow cytometry. Changes in mitochondrial membrane potential were monitored by JC-1 dye. The concentrations of nuclear factor erythroid 2 related factor 2(Nrf2), heme oxygenase-1(HO-1), and nicotinamide adenine dinucleotide phosphatase oxidase 4(Nox4) were measured by Western blot, followed by the assay of Nrf2 concentration changes in cytoplasm and nucleus by confocal fluorescence staining. The results showed that when the concentration of ME was 0-40 µmol·L~(-1), the activity of HK-2 cells was not affected. Compared with the model group, ME enhanced the activity of HK-2 cells and the cell morphology was normal. As revealed by further experiments, ME inhibited the release of reactive oxygen species and the decline in mitochondrial membrane potential of HK-2 cells after H/R injury, promoted Nrf2/HO-1 expression and Nrf2 translocation to the nucleus, and down-regulated the expression of Nox4, thereby significantly reducing apoptosis. This protective effect of ME could be reversed by the specific Nrf2 inhibitor ML385. These findings have preliminarily proved that ME effectively protected HK-2 cells against H/R injury, which might be related to its promotion of Nrf2/HO-1 signaling pathway and inhibition of Nox4. Such exploration on the possible mechanism of ME in the treatment of renal ischemia-reperfusion injury(IRI) and protection of organ function from the perspective of antioxidant stress has provided reference for related research on the treatment of acute kidney injury with traditional Chinese medicine.