Expression pattern of sonic hedgehog and effect of topical mitomycin C on its expression in human ocular surface neoplasms

Shhedding New Light on the Role of Hedgehog Signaling in Corneal Wound Healing

The cornea, an anterior ocular tissue that notably serves to protect the eye from external insults and refract light, requires constant epithelium renewal and efficient healing following injury to maintain ocular homeostasis. Although several key cell populations and molecular pathways implicated in corneal wound healing have already been thoroughly investigated, insufficient/impaired or excessive corneal wound healing remains a major clinical issue in ophthalmology, and new avenues of research are still needed to further improve corneal wound healing. Because of its implication in numerous cellular/tissular homeostatic processes and oxidative stress, there is growing evidence of the role of Hedgehog signaling pathway in physiological and pathological corneal wound healing. Reviewing current scientific evidence, Hedgehog signaling and its effectors participate in corneal wound healing mainly at the level of the corneal and limbal epithelium, where Sonic Hedgehog-mediated signaling promotes limbal stem cell proliferation and corneal epithelial cell proliferation and migration following corneal injury. Hedgehog signaling could also participate in corneal epithelial barrier homeostasis and in pathological corneal healing such as corneal injury-related neovascularization. By gaining a better understanding of the role of this double-edged sword in physiological and pathological corneal wound healing, fascinating new research avenues and therapeutic strategies will undoubtedly emerge.

A front-line window of opportunity phase 2 study of sorafenib in patients with advanced nonsmall cell lung cancer: North Central Cancer Treatment Group Study N0326

BACKGROUND

The current study was conducted to assess the efficacy and toxicity of sorafenib as front-line therapy in patients with stage IIIB (pleural effusion) or IV nonsmall cell lung cancer (NSCLC).

METHODS

Patients received sorafenib 400 mg twice daily by mouth continuously, and were evaluated every 2 weeks during the first 8 weeks. Patients who manifested clinical progression during this period proceeded to receive standard of care. The primary endpoint was confirmed objective tumor response. A 2-stage Fleming design was used such that if at most 1 confirmed partial response (PR) or complete response was observed in the first 20 patients (stage 1), the treatment would be considered ineffective, and further enrollment would be discontinued.

RESULTS

Only 1 PR was observed in the first 20 patients. By the time of study closure, 5 additional patients who were already being screened for study inclusion were enrolled. Of the 25 patients (15 women, 10 men; 4 stage IIIB, 21 stage IV; median age, 67 years [range, 45-85 years]), there were 3 (12%) PRs and 6 (24%) cases with stable disease observed. The median time-to-progression and progression-free survival was 2.8 months. Seven (28%) patients remained progression-free at 24 weeks. No grade 3 or higher hematologic adverse events were observed. Thirteen (52%) patients had a grade 3 nonhematologic adverse event, with fatigue (20%), diarrhea (8%), and dyspnea (8%) being the most common.

CONCLUSIONS

Sorafenib is not effective as front-line therapy in the general unselected NSCLC population. The window of opportunity design is feasible for estimating the activity of novel compounds.

The diagnostic value of exfoliative cytology vs histopathology for ocular surface squamous neoplasia

PURPOSE

To determine the reliability and role of conjunctival exfoliative cytologic and histopathologic diagnosis of biopsied tissue in ocular surface squamous neoplasia.

DESIGN

Retrospective review of an interventional case series of patients biopsied and treated for squamous conjunctival and corneal neoplasia.

METHODS

Forty-nine patients who underwent conjunctival cytologic analysis (n = 36), conjunctival biopsy (n = 35), or both were evaluated. For the purposes of this study, three ocular pathologists reviewed the results of cytologic and biopsied tissue in a masked fashion.

RESULTS

Evaluation of cytologic smears revealed a 91% concordance in interpretation of conjunctival cytologic material as no dysplasia vs dysplasia. The concordance dropped to 59% in grading the degree of dysplasia. The cytologic material was found to be inadequate for interpretation in 1 case. Evaluation of subsequent biopsy revealed a 98% concordance between the pathologists in interpretation of biopsied tissue as no dysplasia vs any degree of dysplasia. The concordance decreased to 83% in grading the degree of dysplasia. Cytologic evaluation was capable of distinguishing a neoplastic from nonneoplastic process before tissue biopsy in 80% of cases.

CONCLUSIONS

Ocular surface cytologic analysis is a simple, safe, and relatively noninvasive diagnostic tool. It was found helpful in detecting dysplasia before surgical resection. It was used in the settings of recurrent tumor and for follow-up care of patients treated with topical chemotherapy. Although cytologic smears cannot replace incisional or excisional biopsy for definitive diagnosis, exfoliative cytologic analysis can play an important role in the diagnosis and management of patients with ocular surface squamous neoplasia.