HPV circulating tumor DNA to monitor the efficacy of anti‐PD‐1 therapy in metastatic squamous cell carcinoma of the anal canal: A case report

Squamous cell carcinoma of the anal canal (SCCA) is a rare HPV‐associated cancer with limited sensitivity to standard chemotherapy. In a phase 2 study, nivolumab, an anti PD‐1 immune checkpoint inhibitor, demonstrated significant efficacy as single‐agent therapy in metastatic SCCA patients. Nevertheless, imaging assessment by standard RECIST criteria of the efficacy of immune therapy can be difficult in some patients due to tumor immune cell infiltration, and biomarkers of treatment efficacy are needed. We have previously developed a quantitative droplet digital PCR (ddPCR) technique to detect HPV circulating tumor DNA (HPV ctDNA), with excellent sensitivity and specificity. Here, we report, for the first time, the kinetics of HPV ctDNA during therapy in a patient with metastatic SCCA, who obtained sustained partial response to single‐agent nivolumab. We observed an early and very significant decrease of HPV ctDNA during therapy from the baseline level of 3713 copies/ml plasma to 564 copies/ml plasma at 4 weeks, and 156 copies/ml at 6 weeks, followed by a plateau. This observation provides proof‐of‐concept that HPV ctDNA can be used as a noninvasive early dynamic biomarker to monitor the efficacy of new immunotherapy agents.     

Two BRM promoter polymorphisms predict poor survival in patients with hepatocellular carcinoma

Polymorphisms in the promoter of the BRM gene, a critical subunit of the chromatin remodeling SWI/SNF complex, have previously been implicated in risk and prognosis in Caucasian‐predominant lung, head and neck, esophageal, and pancreatic cancers, and in hepatocellular cancers in Asians. We investigated the role of these polymorphisms in hepatocellular carcinoma (HCC) risk and prognosis. HCC cases were recruited in a comprehensive cancer center while the matched controls were recruited from family practice units from the same catchment area. For risk analyses, unconditional logistic regression analyses were performed in HCC patients and matched healthy controls. Overall survival analyses were performed using Cox proportional hazard models, Kaplan‐Meier curves, and log‐rank tests. In 266 HCC cases and 536 controls, no association between either BRM promoter polymorphism (BRM‐741 or BRM‐1321) and risk of HCC was identified (P > 0.10 for all comparisons). There was significant worsening of overall survival as the number of variant alleles increased: BRM‐741 per variant allele adjusted hazards ratio (aHR) 5.77, 95% confidence interval (CI) 2.89‐11.54 and BRM‐1321 per variant allele aHR 4.09, 95%CI 2.22‐7.51. The effects of these two polymorphisms were at least additive, where individuals who were double homozygotes for the variant alleles had a 45‐fold increase in risk of death when compared to those who were double wild‐type for the two polymorphisms. Two BRM promoter polymorphisms were strongly associated with HCC prognosis but were not associated with increased HCC susceptibility. The association was strongest in double homozygotes for the allele variants.     

Aromatase inhibitors for infertility in polycystic ovary syndrome. The beginning or the end of a new era?

A meta-analysis of four trials showed significant advantage in pregnancy and delivery rates with aromatase inhibitors compared with CC in women with PCOS. A recent randomized trial demonstrated no clear benefit.     

Treatment of unexplained infertility with aromatase inhibitors or clomiphene citrate: a systematic review and meta-analysis

Treatment of unexplained infertility is empiric and different regimens or protocols have been used so far. Clomiphene can be used alone or combined with gonadotrophins. Aromatase inhibitors may offer an alternative for first-line treatment. To compare the efficacy of aromatase inhibitors versus climiphene, we conducted a systematic review and meta-analysis for randomized controlled trials comparing the above regimens to estimate live pregnancy rates in women with unexplained infertility. Trials were located through PubMed and Cochrane Library searches. Methodological quality of included trials has been assessed. Then, 2 x 2 tables were constructed, and pooled odds ratios (ORs) were calculated. Ten arms (273 patients) were included in the meta-analysis. ORs were homogeneous between studies (heterogeneity chi2 = 2.33, P = 0.676). No difference was observed for live pregnancies (pooled OR 0.87, 95% CI, 0.46-1.65, P = 0.666) for aromatase inhibitors versus clomiphene citrate; however, the definition of live pregnancy by the authors was clear only in one trial. Data regarding secondary outcomes were omitted, and methodogical quality of eligible trials did not reach high scores. Evidence from randomized data regarding the use of aromatase inhibitors is fragmented and weak. Aromatase inhibitors may have a role in the treatment of women with unexplained infertility desiring pregnancy. However, meticulous reporting and study design should be a priority in this field and large, registered, and properly designed randomized trials are essential to test whether aromatase inhibitors can be introduced as a first-line treatment in carefully selected subgroups of women with unexplained infertility.     

Brief Report: Dynamic calcium signals mediate the feeding response of the carnivorous sundew plant

Some of the most spectacular examples of botanical carnivory—in which predator plants catch and digest animals presumably to supplement the nutrient-poor soils in which they grow—occur within the Droseraceae family. For example, sundews of the genus Drosera have evolved leaf movements and enzyme secretion to facilitate prey digestion. The molecular underpinnings of this behavior remain largely unknown; however, evidence suggests that prey-induced electrical impulses are correlated with movement and production of the defense hormone jasmonic acid (JA), which may alter gene expression. In noncarnivorous plants, JA is linked to electrical activity via changes in cytoplasmic Ca²⁺. Here, we find that dynamic Ca²⁺ changes also occur in sundew (Drosera spatulata) leaves responding to prey-associated mechanical and chemical stimuli. Furthermore, inhibition of these Ca²⁺ changes reduced expression of JA target genes and leaf movements following chemical feeding. Our results are consistent with the presence of a conserved Ca²⁺-dependent JA signaling pathway in the sundew feeding response and provide further credence to the defensive origin of plant carnivory.     

Cardiothoracic surgery in South Africa: a history

Cardiothoracic surgery in South Africa began in Cape Town spreading to the rest of the country, and since the end of apartheid slowly reaching other sub-Saharan African countries. It is a story of brilliant innovators, of the evils of the disease of apartheid but also of what is possible if you are determined and prepared to work hard. The early leaders came from the University of Cape Town (UCT) with Christiaan Barnard, Donald Ross and Rodney Hewitson all in the same class of 1946 with Ben Le Roux and Bob Frater soon after. It is a story of world class professionals in a sea of poverty. The heart transplants performed by Barnard stimulated the whole university and eventually had an effect in raising the standard of medicine in South Africa. Despite the apartheid laws at the time the cardiac unit at UCT was run as multiracial as it was possible at the time with all patients receiving the same care. Apartheid also had an effect on the emigration of many highly talented graduates to other countries. The end of apartheid caused great changes to healthcare in the country, many of great benefit but also some not so good. As UCT influenced the rest of South Africa, the South African medical fraternity can affect the rest of sub-Saharan Africa to the benefit of all its people.