Commensal bacteria and fungi differentially regulate tumor responses to radiation therapy

Studies suggest that the efficacy of cancer chemotherapy and immunotherapy is influenced by intestinal bacteria. However, the influence of the microbiome on radiation therapy is not as well understood, and the microbiome comprises more than bacteria. Here, we find that intestinal fungi regulate antitumor immune responses following radiation in mouse models of breast cancer and melanoma and that fungi and bacteria have opposite influences on these responses. Antibiotic-mediated depletion or gnotobiotic exclusion of fungi enhances responsiveness to radiation, whereas antibiotic-mediated depletion of bacteria reduces responsiveness and is associated with overgrowth of commensal fungi. Further, elevated intratumoral expression of Dectin-1, a primary innate sensor of fungi, is negatively associated with survival in patients with breast cancer and is required for the effects of commensal fungi in mouse models of radiation therapy.

Antifungals improve anti-PD1 efficacy in a murine breast cancer model

Every year over 200,000 North American women are diagnosed with breast cancer, which is the second leading cause of cancer death among women. The introduction of effective immunotherapies has revolutionized patient care in many cancers, including breast, but only a subset of patients exhibit clinical response. Factors determining a patient’s response to immunotherapy is an area of intense research. The microbiome is one potential contributing factor. The human intestinal microbiome is comprised largely of bacteria, but also harbors fungi, viruses and archaea that undoubtedly have significant biological functions. Recent reports have detailed the association of specific strains of bacteria with positive response to PD-1/PDL1 therapy in several cancers however, little is known regarding the involvement of commensal fungi. Previous work in our lab found a high diversity of fungi associated with the human gut, which interact with the immune system and influence the severity of gastrointestinal inflammation and allergic airway disease. Using a syngeneic murine model of triple negative breast cancer, we found that antifungal treatment sensitizes previously resistant tumors to anti-PD1 therapy, leading to a significant decrease in growth rate as well as increased survival compared to anti-PD-1 treatment alone. Antifungal treatment altered the microbiome composition as evidenced by 16s and ITS1 sequencing of fecal pellets, as well as altered the tumor immune compartment to promote anti-tumor activity when combined with anti-PD1. These data suggest fungi have a role in shaping the immune-tumor microenvironment and provide insight into how perturbation of the microbiome might improve response to immunotherapy.

Infant CD4 C868T polymorphism is associated with increased human immunodeficiency virus (HIV-1) acquisition

The C868T single nucleotide polymorphism (SNP) in the CD4 receptor encodes an amino acid change that could alter its structure and influence human immunodeficiency virus (HIV-1) infection risk. HIV-1-infected pregnant women in Nairobi were followed with their infants for 1 year postpartum. Among 131 infants, those with the 868T allele were more likely than wild-type infants to acquire HIV-1 overall [hazard ratio (HR) = 1.92, 95% confidence interval (CI) 1.05, 3.50, P = 0.03; adjusted HR = 2.03, 95% CI 1.03, 3.98, P = 0.04], after adjusting for maternal viral load. This SNP (an allele frequency of approximately 15% in our cohort) was associated with increased susceptibility to mother-to-child HIV-1 transmission, consistent with a previous study on this polymorphism among Nairobi sex workers.

Hyperopic laser in situ keratomileusis: primary and secondary treatments are safe and effective

PURPOSE

To retrospectively analyze the safety and efficacy of hyperopic laser in situ keratomileusis (LASIK) treatment of eyes with primary hyperopia and consecutive hyperopia after initial myopic treatment.

METHODS

Thirty-two eyes of 19 patients with primary hyperopia (group 1) and 37 eyes of 26 patients with consecutive hyperopia after initial myopic LASIK overcorrection (group 2) that had LASIK for hyperopia with the Hansatome microkeratome and VISX S2 Smoothscan excimer laser with 6 months' follow-up after surgery were analyzed. Uncorrected visual acuity, best spectacle-corrected visual acuity, fogged manifest refraction, and corneal topography with corneal irregularity measurement (CIM) were evaluated 1 month, 3 months, and 6 months after surgery.

RESULTS

In group 1, the mean preoperative cycloplegic spherical equivalent was +4.0 +/- 4.5 diopters (D) (range, +1.5 to + 8.75 D) and the 6-month postoperative cycloplegic spherical equivalent was +0.26 +/- 1.74 D (range, -3.00 to +2.75 D). Fifty-three percent of eyes (n= 17) in group 1 were within 1 D of emmetropia. Sixty-six percent of eyes (n= 21) had uncorrected visual acuity of at least 20/40. Three eyes (9%) lost two lines of best spectacle-corrected visual acuity. Changes in uncorrected visual acuity, best spectacle-corrected visual acuity, spherical equivalent, and the CIM topographic index 6 months after surgery were statistically significant compared with the preoperative values. In group 2, the mean preoperative cycloplegic spherical equivalent was +1.58 +/- 0.35 D (range, +0.125 to +2.75 D), and the mean postoperative cycloplegic spherical equivalent was -0.48 +/- 0.46 (range, -2.75 to +0.38 D). Eighty-six percent of eyes (n= 32) were within 1 D of emmetropia. Eighty-four percent of eyes (n= 31) in group 2 had uncorrected visual acuity of at least 20/40. One eye (2.7%) lost two lines of best spectacle-corrected visual acuity. Complications included an epithelial nest that resolved 3 months after surgery in one eye in group 2.

CONCLUSIONS

LASIK is a relatively safe treatment of primary hyperopia and hyperopia resulting from overcorrection after initial LASIK treatment of myopia (consecutive hyperopia). Patients with high hyperopia (>5 D) are at risk for loss of two lines of best spectacle-corrected visual acuity. A reduction in the level of attempted correction appears to be necessary in the treatment of consecutive hyperopia.

Primary orbital Ewing sarcoma in a middle-aged woman

A 43-year-old woman had unilateral exophthalmos caused by primary orbital Ewing sarcoma. Specialized immunohistochemical stains, primarily MIC-2 (CD99), aided in the diagnosis of Ewing sarcoma. Twenty-two months after radiotherapy and multiagent chemotherapy, the patient remained tumor free. To our knowledge, this is the first reported case of orbital Ewing sarcoma to present in an adult beyond the fourth decade of life.

The accuracy of experienced strabismologists using the Hirschberg and Krimsky tests

OBJECTIVE

The purpose of the study was to assess the accuracy of a group of strabismologists applying the Hirschberg and Krimsky tests.

DESIGN

A clinical trial.

PARTICIPANTS

Sixteen very experienced strabismologists participated in this study.

INTERVENTION

The participants were asked to evaluate slides of four different patients using the Hirschberg method and to evaluate two of the four patients with the Krimsky method. The slides included a patient with 25 delta left esotropia, a patient with 25 delta right exotropia, a patient with 80 delta esotropia with a positive angle kappa, and a patient with 75 delta infantile esotropia. Alternate prism and cover testing was performed immediately after the photograph was taken and considered to be the actual deviation of the patient.

MAIN OUTCOME MEASURE

Measured was the accuracy in assessing the angle of strabismus.

RESULTS

With the Hirschberg method, each participant underestimated at least one patient by at least 10 delta. In addition, the participants tended to underestimate both large and small angle esotropic and exotropic patients with greater errors of estimation occurring with larger angles of strabismus. With the Krimsky method, a majority of participants overestimated at least one patient by 10 delta and showed difficulty in appreciating differences of 5 delta. In addition, the authors noted inconsistent responses by each participant.

CONCLUSION

The Hirschberg and Krimsky methods are substantially less accurate than the alternate prism and cover test.

Botulinum toxin management of childhood intermittent exotropia

OBJECTIVE

Intermittent exotropia is a common form of childhood strabismus that has a late onset and presents a difficult and frustrating management dilemma. Surgical treatments have a high recurrence rate, and multiple surgeries often are required to achieve a desirable motor outcome. This study presents long-term observations on the use of botulinum toxin for the treatment of intermittent exotropia in children.

DESIGN

This study is a nonrandomized, case-controlled study of consecutive pediatric patients who had intermittent exotropia.

PARTICIPANTS

Thirty-two neurologically normal children ranging from 3 to 144 months in age were diagnosed with intermittent exotropia with a minimum distance deviation of 15 prism diopters (PD).

INTERVENTION

Simultaneous bilateral injections of 2.5 units botulinum toxin type A were made into the lateral rectus muscles with the patient receiving nitrous oxide-ethrane inhalation anesthesia. Patients were observed for 12 to 44 months after the initial injection.

MAIN OUTCOME MEASURES

A satisfactory outcome was considered to be stable binocular alignment of the eyes to an orthophoric range of +/-10 PD.

RESULTS

Bilateral lateral rectus muscle injections of botulinum toxin were effective in reducing the mean preinjection deviation of -29 PD to an average exotropic angle of -6 PD. Stable orthophoria (+/-10 PD) was achieved in 22 patients (69%). Overall, male patients required significantly fewer injections than did female patients. All patients between 24 and 56 months of age, irrespective of gender, required only a single bilateral injection to achieve a favorable motor outcome.

CONCLUSIONS

Botulinum toxin is at least as effective as surgical outcomes reported previously for the treatment of intermittent exotropia in children. This treatment method is particularly effective in children between 2 and 4.5 years of age irrespective of the initial strabismic angle and is not associated with any secondary abnormalities.

Botulinum A toxin treatment of a deviated orbital implant

We report a case of progressive deviation of an implant that resulted in conjunctival thinning and an inadequately fit prosthesis. Such a case may have been treated with conjunctival grafting or replacement of the implant with an hydroxyapatite sphere. In this case, injection of botulinum A toxin (Botox) into the contracted medial rectus muscle contributed to the successful refitting of a new and stable prosthesis and improvement of the conjunctival integrity. Possible explanations of the progressive shift in the position of the implant and its postinjection stability are discussed.