Final analysis of phase II results with cemiplimab in metastatic basal cell carcinoma after hedgehog pathway inhibitors.

BACKGROUND: Metastatic basal cell carcinoma (mBCC) is a rare condition with no effective second-line treatment options. Cemiplimab is an immune checkpoint inhibitor that blocks the binding of programmed cell death-1 (PD-1) to its ligands, programmed death-ligand 1 (PD-L1) and programmed death-ligand 2 (PD-L2). Here, we present the final analysis of cemiplimab in patients with mBCC after first-line hedgehog pathway inhibitor (HHI) treatment (NCT03132636). PATIENTS AND METHODS: In this open-label, single-arm, phase II study, adults with mBCC and Eastern Cooperative Oncology Group performance status ≤1, post-HHI treatment, received cemiplimab 350 mg intravenously every 3 weeks for ≤93 weeks or until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) by independent central review (ICR). Duration of response (DOR) was a key secondary endpoint. Other secondary endpoints were ORR per investigator assessment, progression-free survival (PFS), overall survival (OS), complete response rate, safety, and tolerability. RESULTS: Fifty-four patients were enrolled: 70% were male and the median age of patients was 64 [interquartile range (IQR) 57.0-73.0] years. The median duration of follow-up was 8 months (IQR 4-21 months). The ORR per ICR was 22% [95% confidence interval (CI) 12% to 36%], with 2 complete responses and 10 partial responses. Among responders, the median time to response per ICR was 3 months (IQR 2-7 months). The estimated median DOR per ICR was not reached [95% CI 10 months-not evaluable (NE)]. The disease control rate was 63% (95% CI 49% to 76%) per ICR and 70% (95% CI 56% to 82%) per investigator assessment. The median PFS per ICR was 10 months (95% CI 4-16 months); the median OS was 50 months (95% CI 28 months-NE). The most common treatment-emergent adverse events were fatigue [23 (43%)] and diarrhoea [20 (37%)]. There were no treatment-related deaths. CONCLUSIONS: Cemiplimab demonstrated clinically meaningful antitumour activity, including durable responses, and an acceptable safety profile in patients with mBCC who had disease progression on or intolerance to HHI therapy.

Chronic interstitial granulomatous dermatitis in coccidioidomycosis.

Coccidioides species are soil-dwelling fungi endemic to the Southwest U.S.A., especially Arizona and California and Northern Mexico. The cutaneous findings of coccidioidomycosis have a wide range of pathology, which includes organism-specific and reactive processes. Interstitial granulomatous dermatitis (IGD), a granuloma annulare-like reaction, has been described, in a limited form, in association with acute pulmonary coccidioidomycosis. We present a case of chronic, widespread IGD spanning over 9 years in association with an active coccidioidomycosis infection. Similar clinical and histopathological features have been described in association with drug reactions, connective tissue diseases, systemic vasculitis, lymphomas, other infectious diseases and inflammatory bowel disease. Our patient's dramatic presentation and chronic course expands upon the clinical spectrum of IGD occurring in association with pulmonary coccidioidomycosis. While IGD in association with coccidioidomycosis is rare, both dermatologists and general practitioners see IGD reactions, and our case highlights the importance of identifying the underlying driver.

Activating BRAF mutations in eruptive melanocytic naevi.

BACKGROUND: Eruptive melanocytic naevi (EMN) are melanocytic proliferations developing rapidly on previously unaffected skin in association with various clinical scenarios, most commonly systemic immunosuppression. However, the exact mechanism leading to development of EMN is not understood. In particular, it is not known whether EMN harbour the BRAF mutations which occur frequently in melanoma and most common naevi. OBJECTIVES: To evaluate whether activating BRAF mutations may play a role in genesis of EMN. METHODS: Genomic DNA was isolated from 20 EMN from a patient treated with 6-mercaptopurine (6-MP). Primary BRAF genotyping was performed by allelespecific polymerase chain reaction, followed by validation using direct sequencing. RESULTS: The BRAF V600E mutation was identified in 85% of EMN examined. CONCLUSIONS: Our results implicate mutational activation of the BRAF­MAPK pathway as a factor in development of EMN in the setting of 6-MP treatment. The mechanism leading to development of EMN in this, and potentially other patients, may relate to synergistic mutagenic effects of thioguanines and ultraviolet (UV) A. Together with the documented importance of BRAF mutations in melanoma development and maintenance, these findings highlight the importance of UVA protection, especially in patients treated with thiopurines such as 6-MP.

Phosphorylation of the translational repressor PHAS-I by the mammalian target of rapamycin.

The immunosuppressant rapamycin interferes with G1-phase progression in lymphoid and other cell types by inhibiting the function of the mammalian target of rapamycin (mTOR). mTOR was determined to be a terminal kinase in a signaling pathway that couples mitogenic stimulation to the phosphorylation of the eukaryotic initiation factor (eIF)-4E-binding protein, PHAS-I. The rapamycin-sensitive protein kinase activity of mTOR was required for phosphorylation of PHAS-I in insulin-stimulated human embryonic kidney cells. mTOR phosphorylated PHAS-I on serine and threonine residues in vitro, and these modifications inhibited the binding of PHAS-I to eIF-4E. These studies define a role for mTOR in translational control and offer further insights into the mechanism whereby rapamycin inhibits G1-phase progression in mammalian cells.

Metastatic malignant melanoma.

Metastatic malignant melanoma is an incurable malignancy with extremely poor prognosis. Patients bearing this diagnosis face a median survival time of approximately 9 months with a probability of surviving 5 years after initial presentation at less than 5%. This is contrasted by the curative nature of surgical resection of early melanoma detected in the skin. To date, no systemic therapy has consistently and predictably impacted the overall survival of patients with metastatic melanoma. However, in recent years, a resurgence of innovative diagnostic and therapeutic developments have broadened our understanding of the natural history of melanoma and identified rational therapeutic targets/strategies that seem poised to significantly change the clinical outcomes in these patients. Herein we review the state-of-the-art in metastatic melanoma diagnostics and therapeutics with particular emphasis on multi-disciplinary clinical management.

A direct linkage between the phosphoinositide 3-kinase-AKT signaling pathway and the mammalian target of rapamycin in mitogen-stimulated and transformed cells.

The microbially derived antiproliferative agent rapamycin inhibits cell growth by interfering with the signaling functions of the mammalian target of rapamycin (mTOR). In this study, we demonstrate that interleukin-3 stimulation induces a wortmannin-sensitive increase in mTOR kinase activity in a myeloid progenitor cell line. The involvement of phosphoinositide 3'-kinase (PI3K) in the regulation of mTOR activity was further suggested by findings that mTOR was phosphorylated in vitro and in vivo by the PI3K-regulated protein kinase, AKT/PKB. Although AKT phosphorylated mTOR at two COOH-terminal sites (Thr2446 and Ser2448) in vitro, Ser2448 was the major phosphorylation site in insulin-stimulated or -activated AKT-expressing human embryonic kidney cells. Transient transfection assays with mTOR mutants bearing Ala substitutions at Ser2448 and/or Thr2446 indicated that AKT-dependent mTOR phosphorylation was not essential for either PHAS-I phosphorylation or p70S6K activation in HEK cells. However, a deletion of amino acids 2430-2450 in mTOR, which includes the potential AKT phosphorylation sites, significantly increased both the basal protein kinase activity and in vivo signaling functions of mTOR. These results demonstrate that mTOR is a direct target of the PI3K-AKT signaling pathway in mitogen-stimulated cells, and that the identified AKT phosphorylation sites are nested within a "repressor domain" that negatively regulates the catalytic activity of mTOR. Furthermore, the activation status of the PI3K-AKT pathway in cancer cells may be an important determinant of cellular sensitivity to the cytostatic effect of rapamycin.

Ischaemic colitis--review.

Colonic ischaemia, commonly referred to as ischaemic colitis, is the most common type of intestinal ischaemia. The term "ischaemic colitis" was used by Marston (1966) with three typical patterns of injury described: transient reversible ischaemia, ischaemic ulcers with stricturing, and gangrenous ischaemic colitis. Dominant presenting symptoms were colicky abdominal pain, vomiting, bloody diarrhea, and hematochezia. Patients often have minimal signs on clinical examination. Most patients were diagnosed at colonoscopy. Two regions that are believed to be anatomically vulnerable to ischemic disease are "Griffith's point", at the splenic flexure and "Sudeck's critical point", of the Drummond marginal artery. Clinically, ischaemic colitis is classified as non-gangrenous or gangrenous. Non-gangrenous ischaemic colitis involves the mucosa and submucosa and accounts for 80-85 percent of all cases of ischaemic colitis. Non-gangrenous ischaemic colitis is further subclassified into transient, reversible ischaemic colitis with a less severe form of injury and chronic, non-reversible ischaemic colitis, which includes chronic colitis and stricture and has a more severe form of injury. Gangrenous ischaemic colitis accounts for the remaining 15-20 percent of cases and manifests as the most seve-re form of injury. It includes acute fulminant ischaemia with transmural infarction that may progress to necrosis and death. Specific indications for operation include peritonitis, perforation, recurrent fever or sepsis, clinical deterioration in patients refractory to me-ical management. Relative indications include fulminant colitis, massive hemorrhage, chronic protein losing colopathy, and symptomatic ischemic stricture.

Endorectal ultrasound (ERUS) in pelvic disorders.

Endorectal ultrasound (ERUS) imaging is a complex process using electronic devices to control ultrasound waves and produce images of anatomic structures. It is a simple, cheep and well-tolerated procedure that provides excellent images of rectal and anal canal wall and pelvic floor muscles together with surrounding organs and tissues. The direct imaging of anal canal and pelvic floor muscles with surrounding tissues allows one to identify sphincter defects, anorectal abscesses and fistulas as well as great variety of benign and malignant pathology of the pelvis. Basically, techniques for ERUS are very similar, but there are some slight modifications regarding equipment, indications, and localization of pathologic process. We describe the technique, indications, results and pitfalls of ERUS with the Bruel and Kjaer type 1850 endosonic probe with 7 and 10 MHz transducers in benign pelvic disorders.

Hansenula anomala outbreak at a surgical intensive care unit: a search for risk factors.

During a 5-month period, Hansenula anomala (H. anomala), an opportunistic fungus, caused an outbreak of infections in eight adult patients treated at a surgical intensive care unit (ICU). The source of the infections and route of transmission could not be identified. A case-control study included 32 patients treated simultaneously at the surgical ICU. Univariate analysis pointed to the following significant risk factors: blood alkalosis, reduced urea, duration of hospitalization, bacteremia and colonization with Pseudomonas aeruginosa, and an APACHE II score >17 (during bacteremia or fungemia). The stepwise logistic regression multivariate analysis showed only the duration of blood alkalosis to be significant in case patients.

Polyomavirus middle T antigen as a probe for T cell antigen receptor-coupled signaling pathways.

Stimulation of the T cell antigen receptor (TCR) triggers a complex series of signaling events that culminate in T cell activation and proliferation. The complex structure of the TCR has hindered efforts to link specific signaling events induced by TCR cross-linkage to downstream activation responses, such as interleukin-2 (IL-2) gene transcription. Previous studies have shown that the polyomavirus-derived oncoprotein, middle T antigen (mT), transforms rodent fibroblasts by interacting with and activating several cytoplasmic signaling proteins (Src kinases, phospholipase C (PLC)-gamma1, Shc, and phosphoinositide 3-kinase (PI3-K) implicated in cell growth control. In this study, we demonstrate that expression of mT activates Jurkat T cells, as measured by increases in IL-2 promoter- and NFAT (nuclear factor of activated T cells)-dependent reporter gene transcription. The transcriptional response provoked by mT was blocked by the immunosuppressive drug FK506, a potent inhibitor of TCR-mediated IL-2 gene expression. Mutations that disrupted the binding of mT to Src kinases or PLC-gamma1 abrogated the ability of mT to deliver the signals needed for IL-2 promoter activation. In contrast, a mT mutant that failed to bind PI3-K induced a markedly elevated transcriptional response in Jurkat cells, whereas mutation of the Shc binding site in mT had little effect on the transactivating potential of this viral oncoprotein. Additional studies demonstrated that the association of mT with PLC-gamma1 was necessary and sufficient to activate both Ca2+- and Ras-dependent signaling cascades in Jurkat cells. These results indicate that PLC-gamma1 activation plays pivotal and pleiotropic roles in the stimulation of IL-2 gene expression, whereas activation of PI3-K negatively modulates this response in Jurkat T cells.

Studies on the mechanism of resistance to rapamycin in human cancer cells.

Rapamycin is a potent cytostatic agent that arrests cells in the G1 phase of the cell cycle. The relationships between cellular sensitivity to rapamycin, drug accumulation, expression of mammalian target of rapamycin (mTOR), and inhibition of growth factor activation of ribosomal p70S6 kinase (p70(S6k)) and dephosphorylation of pH acid stable protein I (eukaryotic initiation factor 4E binding protein) were examined. We show that some cell lines derived from childhood tumors are highly sensitive to growth inhibition by rapamycin, whereas others have high intrinsic resistance (>1000-fold). Accumulation and retention of [14C]rapamycin were similar in sensitive and resistant cells, with all cells examined demonstrating a stable tight binding component. Western analysis showed levels of mTOR were similar in each cell line (<2-fold variation). The activity of p70(S6k), activated downstream of mTOR, was similar in four cell lines (range, 11.75-41. 8 pmol/2 x 10(6) cells/30 min), but activity was equally inhibited in cells that were highly resistant to rapamycin-induced growth arrest. Rapamycin equally inhibited serum-induced phosphorylation of pH acid stable protein I in Rh1 (intrinsically resistant) and sensitive Rh30 cells. In serum-fasted Rh30 and Rh1 cells, the addition of serum rapidly induced c-MYC (protein) levels. Rapamycin blocked induction in Rh30 cells but not in Rh1 cells. Serum-fasted Rh30/rapa10K cells, selected for high level acquired resistance to rapamycin, showed >/=10-fold increased c-MYC compared with Rh30. These results suggest that the ability of rapamycin to inhibit c-MYC induction correlates with intrinsic sensitivity, whereas failure of rapamycin to inhibit induction or overexpression of c-MYC correlates with intrinsic and acquired resistance, respectively.