Effectiveness and Safety of a New Hyaluronic Acid Injectable for Augmentation and Correction of Chin Retrusion

BACKGROUND

A hyaluronic acid (HA) filler intended for non-surgical improvement of chin appearance should ideally be of high strength/firmness (high G') to allow for deep injections on the bone. HASHA (Restylane Shaype) is a new hyaluronic acid (HA) injectable with high G' and high HA concentration (25 mg/mL), engineered by the new NASHA-HD (High Definition) technology. HASHA is suitable to be placed periosteally, aiming to mimic the natural shape of the bony chin. This pivotal clinical investigation evaluated effectiveness and safety of HASHA for augmentation and correction of chin retrusion.  Methods: Subjects 18 years or older with mild or moderate chin retrusion by the Galderma Chin Retrusion Scale (GCRS), were randomized 3:1 to HASHA (n=103) or no treatment (n=37). Assessments included GCRS (blinded evaluator), aesthetic improvement (Global Aesthetic Improvement Scale [GAIS]), subject satisfaction, and safety.  Results: GCRS responder rate (1-grade or greater improvement from baseline) was significantly higher for HASHA (83.3%) versus controls (10.8%) at month 3 (P<0.001) and maintained through month 12 (P<0.001). Aesthetic improvement was high throughout the study in the HASHA group, according to investigators (97% or greater) and subjects (89% or greater). Overall, subject satisfaction was high at month 3 and maintained at month 12. Product- or injection-related adverse events were mostly mild or moderate and transient. No product- or injection-related serious adverse events were reported.

CONCLUSIONS

HASHA, a new NASHA-HD injectable with extra strength/firmness, was safe and effective for chin augmentation and correction of chin retrusion, with high aesthetic improvement and subject satisfaction throughout 12 months. J Drugs Dermatol. 2024;23(4):255-261.     doi:10.36849/JDD.8145.

Skin care and hygiene among healthcare professionals during and after the SARS-CoV-2 pandemic

The severe acute respiratory syndrome coronavirus 2 pandemic has necessitated enhanced protection against viral transmission among healthcare professionals, particularly relating to handwashing and personal protective equipment. Some of these requirements may persist for years to come. They bring associated concerns around skin hygiene and general care, with damage to the face and hands now a well-documented consequence among healthcare professionals. This review assesses optimal skin care during the severe acute respiratory syndrome coronavirus 2 pandemic and in the "new normal" that will follow, identifies current knowledge gaps, and provides practical advice for the clinical setting. Regular, systematic hand cleaning with soap and water or an alcohol-based hand rub (containing 60%-90% ethanol or isopropyl alcohol) remains essential, although the optimal quantity and duration is unclear. Gloves are a useful additional barrier; further studies are needed on preferred materials. Moisturization is typically helpful and has proven benefits in mitigating damage from frequent handwashing. It may be best practiced using an alcohol-based hand rub with added moisturizer and could be particularly important among individuals with pre-existing hand dermatoses, such as psoriasis and eczema. Face moisturization immediately prior to donning a mask, and the use of dressings under the mask to reduce friction, can be helpful dermatologically, but more work is required to prove that these actions do not affect seal integrity. Nonetheless, such measures could play a role in institutional plans for mitigating the dermatologic impact of transmission control measures as we exit the pandemic.

Injectable DaxibotulinumtoxinA for the Treatment of Glabellar Lines: A Phase 2, Randomized, Dose-Ranging, Double-Blind, Multicenter Comparison With OnabotulinumtoxinA and Placebo

BACKGROUND

Injectable daxibotulinumtoxinA (RT002) is an investigational botulinum toxin Type A in clinical development. It is formulated with a proprietary peptide and offers the potential of a longer acting neurotoxin therapy.

OBJECTIVE

To compare the safety, efficacy, and duration of response of daxibotulinumtoxinA with onabotulinumtoxinA and placebo [www.clinicaltrials.gov NCT02303002].

METHODS

In this Phase 2, randomized, dose-ranging, parallel-group, double-blind, multicenter study, subjects with moderate or severe glabellar lines at maximum frown were randomly assigned to 20U, 40U, or 60U daxibotulinumtoxinA, 20U onabotulinumtoxinA, or placebo. Glabellar line severity was evaluated by investigators and subjects at least every 4 weeks, for at least 24 weeks.

RESULTS

Overall, 268 subjects enrolled. Statistical and clinical superiority were observed for 40U and 60U daxibotulinumtoxinA over 20U onabotulinumtoxinA for a range of efficacy outcomes despite the study not being powered to detect statistically significant differences between these active treatment groups.

CONCLUSION

The 40U dose of daxibotulinumtoxinA was well tolerated (e.g., absence of ptosis) and had the most favorable risk: benefit profile. Compared with 20U onabotulinumtoxinA, it exhibited a significantly greater response rate and a significantly longer duration of response (median of 24 weeks vs 19 weeks; p = .030).

Primary Systemic Amyloidosis Presenting as Extensive Cutaneous Ulceration

Background:

We report a case of primary systemic amyloidosis in a 78-year-old Caucasian woman presented as a nonhealing ulcer on the right thigh for 3 months. Histopathology of the skin revealed widely thickened walls of middermal and subcutaneous vessels from deposition of amorphous eosinophilic material that stained positively with Congo red and crystal violet.

Objective:

This case represents a very unusual presentation of primary systemic amyloidosis, one in which the cutaneous manifestations provided the first signs of a devastatingly widespread multiorgan infiltration of amyloid protein.

Conclusion:

This presentation of the disease may signify an advanced stage with a grave prognosis as our patient passed away 3 months after development of the cutaneous ulceration.

Abstract PD1-8: Acquired resistance to rapamycin and mTOR kinase inhibitors is mediated by non-overlapping mutations in distinct sites in the mTOR protein

The mammalian target of rapamycin (mTOR) protein kinase regulates protein translation and proliferation by integrating the availability of energy, nutrients and the presence of growth factors. Dysregulation of mTOR is a common event in human tumors and results from mutational activation of receptor tyrosine kinases, PI3K signaling or inactivating mutations of the Tuberous Sclerosis or GATOR complexes as well as the LKB/AMP kinase pathway.

The prevalence of mTOR activation in cancer has led to the development of two classes of inhibitors of the protein as therapeutics: the natural product rapamycin and its analogs as well as direct inhibitors of mTOR kinase. mTOR exists in at least two multi-protein complexes. The mTORC1 complex phosphorylates S6K and 4EBP and stimulates protein translation, metabolism as well as other processes. The mTORC2 complex phosphorylates and activates AKT and other AGC kinases. Rapamycin binds to the immunophilin FKBP12. Drug-bound FKBP12 complex binds to mTOR FRB domain and selectively inhibits the activity of mTORC1. However, rapalogs preferentially inhibit S6K phosphorylation compared to 4EBP phosphorylation. Rapalogs have undergone extensive clinical testing and have significant antitumor activity in renal cell and pancreatic neuroendocrine tumors and, in combination with aromatase inhibitors, in resistant, ER positive breast cancers. In contrast, mTOR kinase inhibitors suppress both mTORC1 and mTORC2 functions and potently inhibit S6K, 4EBP and AKT S473 phosphorylation. These drugs are in early clinical testing.

In order to better understand the mechanism of action of these drugs and potential mechanisms of tumor escape from mTOR inhibition, we selected breast tumor cells for resistance to growth inhibition in cell culture by treatment with either rapamycin or an mTOR kinase inhibitor. In rapamycin resistant cells, phosphorylation of S6K and S6 were insensitive to the drug, but remained sensitive to mTOR kinase inhibitors. Conversely, in clones resistant to mTOR kinase inhibitors, mTORC1 and mTORC2 substrates were insensitive to the drugs, but S6K and S6 phosphorylation remained sensitive to rapamycin. Deep sequencing results explained these findings: rapamycin resistant clones harbored mutations in the FRB domain of mTOR, in the sites shown to interact with the FKBP12-rapamycin complex; mTOR kinase resistant clones harbored mutations in the mTOR catalytic domain. These mutations were not observed in the parental cells. It is likely that the mutations identified in each domain prevent binding of the drug.

Consistent with these data, growth of rapamycin resistant cells retain sensitivity to mTOR kinase inhibitors and mTOR kinase resistant cells retain sensitivity to rapalogs, both in tissue culture and in vivo. The results suggest that tumor cells with acquired resistance to mTOR inhibitors retain a requirement for mTOR signaling for proliferation. Furthermore, tumors resistant to either class of drug may not be cross-resistant to the other and combined therapy with both might delay the onset of resistance. Further studies on the genetics of human tumors with acquired resistance to these agents will determine the clinical importance of these findings.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr PD1-8.

Image based feasibility of renal sparing surgery for very low risk unilateral Wilms tumors: a report from the Children's Oncology Group

PURPOSE

Nephrectomy with lymph node sampling is the recommended treatment for children with unilateral Wilms tumor under the Children's Oncology Group protocols. Using radiological assessment, we determined the feasibility of performing partial nephrectomy in a select group of patients with very low risk unilateral Wilms tumor.

MATERIALS AND METHODS

We reviewed imaging studies of 60 patients with a mean age of less than 2 years with very low risk unilateral Wilms tumor (mean weight less than 550 gm) to assess the feasibility of partial nephrectomy. We evaluated percentage of salvageable parenchyma, tumor location and anatomical features preventing a nephron sparing approach.

RESULTS

A linear relationship exists between tumor weight and computerized tomography estimated tumor volume. Mean tumor weight in the study population was 315 gm. Partial nephrectomy was deemed feasible in only 5 of 60 patients (8%).

CONCLUSIONS

When considering a select population with very low risk unilateral Wilms tumor (lower volume tumor), only a small percentage of nonpretreated patients are candidates for nephron sparing surgery.

Abstract P4-08-02: Reactivation of oncogenic signaling through mTOR inhibitors-induced feedback adaptations

mTORC1 inhibitors (or rapalogs) relieve feedback inhibition of receptor tyrosine kinases (RTKs) and cause mTORC2-dependent phosphorylation of AKT S473 and activation of AKT kinase and signaling. The relief of feedback inhibition of mTORC2/AKT signaling has been shown to abolish the antitumor activity of rapalogs and has often been proposed as a potential mechanism of resistance to these compounds.

mTOR kinase inhibitors that inhibit both mTORC1 and mTORC2 complexes have now been developed to circumvent these problems. mTOR kinase inhibitors block mTORC1 and mTORC2 and thus, do not cause the mTORC2 activation of AKT observed with rapamycin. We now show, however, that these novel classes of drugs have a biphasic effect on AKT. Inhibition of mTORC2 leads to AKT S473 dephosphorylation and a rapid but transient inhibition of AKT T308 phosphorylation and AKT signaling. However, inhibition of mTOR kinase, as observed with rapalogs, also relieves feedback inhibition of RTKs leading to subsequent PI3K activation and rephosphorylation of AKT but only at T308, which is sufficient to reactivate AKT activity and signaling. Thus, catalytic inhibition of mTOR kinase leads to a new steady state characterized by profound inhibition of mTORC1 and accumulation of activated AKT phosphorylated on T308 but not S473.

We now confirm that the reactivation of AKT signaling is a mechanism of acquired resistance to rapalogs. We observe an induction of phospho-RTKs in rapamycin-resistant cells leading to both AKT and ERK signaling pathway activation enhancing cell survival. Combined inhibition of mTOR and the induced RTKs can prevent AKT reactivation and fully abolishes AKT signaling. These results reveal the adaptive capabilities of oncogenic signaling networks, highlighting the possible need for combinatorial approaches to block feedback-regulated pathways.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P4-08-02.

The evolving role of hyaluronic acid fillers for facial volume restoration and contouring: a Canadian overview

Recent advancements, including more versatile facial fillers, refined injection techniques and the adoption of a global facial approach, have contributed to improved patient outcome and increased patient satisfaction. Nine Canadian specialists (eight dermatologists, one plastic surgeon) collaborated to develop an overview on volume restoration and contouring based on published literature and their collective clinical experience. The specialists concurred that optimal results in volume restoration and contouring depend on correcting deficiencies at various layers of the facial envelope. This includes creating a foundation for deep structural support in the supraperiosteal or submuscular plane; volume repletion of subcutaneous fat compartments; and the reestablishment of dermal and subdermal support to minimize cutaneous rhytids, grooves and furrows. It was also agreed that volume restoration and contouring using a global facial approach is essential to create a natural, youthful appearance in facial aesthetics. A comprehensive non-surgical approach should therefore incorporate combining fillers such as high-viscosity, low-molecular-weight hyaluronic acid (LMWHA) for structural support and hyaluronic acid (HA) for lines, grooves and furrows with neuromodulators, lasers and energy devices.

The usefulness of the bilobed flap for lateral cheek defects

The cheek and nose are common areas for skin cancers. There are multiple approaches to surgical excision and reconstruction, depending on the size of defect, tissue quality, adjacent cosmetic units and hairline. An effective solution to skin defects of the lateral cheek is the bilobed flap. This flap tends to be underused in the lateral cheek area because primary closure and skin grafts are perceived to be easier methods of reconstruction. However, the use of the bilobed flap for lateral cheek and other defect closures is encouraged. There are several basic principles that are key when performing this flap. These components of the procedure are highlighted.

The usefulness of the bilobed flap for lateral cheek defects

The cheek and nose are common areas for skin cancers. There are multiple approaches to surgical excision and reconstruction, depending on the size of defect, tissue quality, adjacent cosmetic units and hairline. An effective solution to skin defects of the lateral cheek is the bilobed flap. This flap tends to be underused in the lateral cheek area because primary closure and skin grafts are perceived to be easier methods of reconstruction. However, the use of the bilobed flap for lateral cheek and other defect closures is encouraged. There are several basic principles that are key when performing this flap. These components of the procedure are highlighted.

Pathway to Dry Skin Prevention and Treatment

Background:

This article presents an evidence-supported clinical pathway for dry skin prevention and treatment.

Objective:

The development of the pathway involved the following: a literature review was conducted and demonstrated that literature on dry skin is scarce. To compensate for the gap in the available literature, a modified Delphi method was used to collect information on prevention and treatment practice through a panel, which included 10 selected dermatologists who currently provide medical care for dermatology patients in Ontario. An advisor experienced in this therapeutic area guided the process, including a central meeting. Panel members completed a questionnaire regarding their individual practice in caring for these patients and responded to questions on assessment of dry skin etiology, frequency of skin care visits for consultation and follow-up, assessment, and referral to other specialties. The panel members reviewed a summary of all responses and reached a consensus. The result was presented as a clinical pathway.

Conclusion:

The panel concluded that our current awareness of dry skin and therefore prevention and effective treatment is limited; that identifying dry skin and its clinical issues requires tools such as clinical pathways, which may improve patient outcomes; and that additional research on dry skin etiology, prevention, and treatment is necessary.

Abstract P4-06-07: PI3K Mutations Are More Common in Low Grade DCIS

Background: DCIS is a non-obligate precursor to invasive breast cancer yet it remains difficult to predict which lesions will progress or over what time interval. Factors associated with a higher risk of progression include high histologic grade and HER2 amplification. HER2 signaling via the PI3K pathway is associated with accelerated invasiveness in laboratory models and mutations in the helical domain of PI3K have been associated with a worse prognosis in invasive cancer. We hypothesized that PI3K pathway mutations are associated with higher risk of progression in DCIS and therefore would be more common in high grade DCIS.

Methods: 195 cases of pure DCIS were identified from the MSKCC breast service database (1999-2003). All cases were reviewed by a single pathologist to assign histologic grade. Sections were obtained from archived formalin-fixed paraffin embedded (FFPE) blocks for manual microdissection to isolate pure DCIS lesions for DNA extraction. Multiplex array (Sequenom®) genotyping for PIK3CA was performed on prePCR amplified DNA. Comparisons were made between high and low grade DCIS using Fisher's exact test.

Results: Among 195 pure DCIS cases, 89 were classified as high grade and 106 as low grade. Sequenom® analysis was informative in all cases. PIK3CA mutations were identified in 4/89 (4%) cases of high grade DCIS and in 24/106 (23%) cases of low grade DCIS (p=0.000). All 4 mutations in high grade DCIS were located in the kinase domain, whereas in low grade DCIS, 9/24 (37%) mutations were in the kinase domain (H1047R) and 15/24 (67%) mutations were in the helical domain (E542K, E545K, N345K).

Conclusion: PI3K mutations were relatively uncommon in pure high grade DCIS as compared to low grade DCIS. PI3K mutations in low grade DCIS were observed in both the kinase and helical domain. These findings support the hypothesis that breast tumorigenesis differs by grade and PI3K mutations may be more prominent in low grade carcinogenesis. The significance of helical domain mutations in low grade lesions requires further investigation.

Current management of actinic keratoses

An actinic keratosis (AK) is a pre-malignant cutaneous lesion that frequently manifests in sun-exposed areas of the skin as a small, rough, scaly erythematous papule. They are one of the most common presenting complaints for dermatologists. AKs should be treated due to their potential to progress into a squamous cell carcinoma (SCC). There are numerous treatments available for managing AKs including those broadly categorized as destructive, topical field, and procedural field therapies. The topical field therapies include 5-fluorouracil, imiquimod, and diclofenac gel. Recently, imiquimod 3.75% (Zyclara TM) has been approved for the treatment AKs on the face and scalp. It is a reasonable alternative to imiquimod 5%, as the approved indication includes a larger surface area for treatment, shorter duration course, and the potential for less severe local skin reactions. There is no widely accepted algorithm for the treatment of AKs, as comparative data is unavailable between all approaches. Therapy choices are guided by efficacy, adverse effects, cosmetic results, and patient compliance.

Extracellular cleaved HER2 (p95) confers partial resistance to trastuzumab but not HSP90 inhibitors in models of HER2 amplified breast cancer

10515

Background: Breast cancers containing an amplified copy of the HER2 receptor tyrosine kinase represent 20–30% of all cases and antibody directed therapy targeting the extracellular domain of HER2 with trastuzumab has proven broadly efficacious. However, resistance to trastuzumab is a common phenomenon. Recent work has identified a cleaved, 95kD version of HER2 that lacks the extracellular epitope in which the trastuzumab binding site is found. Presence of this so called “p95” has been correlated with a worse clinical prognosis. We hypothesized that p95 may enable tumor resistance to trastuzumab. Methods/Results: We established models of p95 expressing breast cancer by transfecting p95 into preexisting models of HER2 amplified breast cancer. We find that cells expressing p95 display increased resistance to the growth inhibitory effects of trastuzumab. The PI3K-AKT pathway that is downregulated by Trastuzumab is less affected in the p95 expressing cells. Furthermore, p95 demonstrates an association with HER3 that is unaffected by trastuzumab treatment. Next, we evaluated the efficacy of therapies targeted against the intracellular domain of HER2 such as the HSP90 inhibitor, 17-AAG. HER2 requires HSP90 for its conformational stability and inhibitors of HSP90 result in growth inhibition of HER2+ breast cancer. We find that p95 displays a similar requirement for HSP90 as inhibitors of HSP90 result in the degradation of p95. Moreover, cells overexpressing p95 are equally susceptible to the antitumor effects of HSP90 inhibitors as those without high levels of p95. Finally, we utilized an empirically derived, in vivo model of trastuzumab resistance that displays high level expression of p95. As with the transfected models, these tumors retain their sensitivity to HSP90 inhibitors as treatment of mice bearing tumors results in both degradation of HER2 and p95 as well as robust tumor growth inhibition. Conclusions: Given the presence of p95 in human breast tumor samples, the data suggest that p95 may play an important role in mediating clinical resistance to trastuzumab. They further suggest that such tumors may retain their sensitivity to targeted therapy against the intracellular portion of HER2 such as with lapatinib or 17-AAG.

No significant financial relationships to disclose.

BRAF mutation predicts MEK-dependence in non-small cell lung cancer (NSCLC)

10523

Background: Constitutive ERK signaling is common in human cancer and is often the result of activating mutations in BRAF, RAS and upstream receptors. Missense BRAF kinase domain mutations are frequently observed in melanoma, colon and thyroid cancers and less frequently in lung and other cancer types. The vast majority (>90%) involve a glutamic acid for valine substitution at codon 600 (V600E), which results in elevated BRAF kinase activity. BRAF kinase domain mutations with intermediate and impaired kinase activity have also been identified, most frequently in NSCLC. We have previously reported that tumors with V600E BRAF mutation are selectively sensitive to MEK inhibition. Methods: Using the potent and selective MEK1/2 inhibitor PD0325901 (Pfizer), we examined a panel of NSCLC cell lines with mutant EGFR, KRAS, and/or low, intermediate and high-activity BRAF kinase domain mutations, with regard to MEK dependence. In all but one case, EGFR, KRAS and BRAF mutations were mutually exclusive. Results: Consistent with our prior results, NSCLC cells with V600E BRAF mutation were exquisitely sensitive to MEK inhibition (PD0325901 IC50 of 2nM). The proliferation of cells with non-V600E mutations, including those with high (G469A), intermediate (L597V) and impaired (G466V) kinase activities, was also MEK dependent with IC50's ranging between 2.7 and 80 nM. Inhibition of MEK in these cells resulted in downregulation of cyclin D1 and G1 growth arrest, with variable induction of apoptosis. Despite high basal ERK activity, NSCLC tumor cells with EGFR mutation were uniformly resistant to MEK inhibition (at doses of up to 500nM), despite effective inhibition of ERK phosphorylation. Tumor cells with RAS mutation had a more variable response, with some cell lines demonstrating sensitivity, while others were completely resistant. There was no correlation between basal ERK activity and sensitivity to MEK inhibition. A strong inverse correlation between AKT phosphorylation/ activity and PD0325901 sensitivity was observed. Conclusions: These results suggest that MEK inhibition may be useful therapeutically in tumors with V600E and non-V600E BRAF kinase domain mutations. The results also suggest that inhibition of both MEK and AKT signaling may be required in NSCLC tumors with high basal AKT activity.

No significant financial relationships to disclose.

Induction of complete regressions of oncogene-induced breast tumors in mice

Over the past decade, mouse models of cancer have come to resemble human disease much more closely than simple subcutaneous or orthotopic systems. Intervention strategies that work on these new model systems are more likely to have an impact clinically. We have shown recently that antiangiogenic stress imposed by loss of Id protein in endothelial progenitor cells results in dramatic central necrosis in breast tumors initiated in mice by overexpression of the her2/neu oncogene. Tumor cells remain viable at the periphery, perhaps via the hypoxic response pathway which allows the lesions to expand. Inhibition of this pathway by the inactivation of the Hif-1alpha chaperone Hsp90 in combination with antiangiogenic stress leads to the first reported complete regression of these aggressive breast tumors.

A phase I/II trial of RAD 001 with gefitinib in patients with castrate metastatic prostate cancer and glioblastoma multiforme

14520

Background: Inactivation of the Pten tumor suppressor gene, leading to constitutive activation of the PI3K/AKT/mTOR pathway, is correlated with resistance to EGFR-targeted therapies. This trial tested the concept that inhibition of mTOR by RAD 001 (NOVARTIS) will restore sensitivity to EGFR inhibition by gefitinib (ASTRA ZENECA), in patients with progressive PC and GBM. Methods: Phase I was designed to determine a safe and tolerable dose and the pharmacokinetics (PK) of RAD (30/ 50/ 70 mg po weekly) with a fixed dose of gefitinib (250 mg po qd) in patients with PC and GBM. Phase II evaluated the proportion of PC patients with no change or a decline in PSA at 12 weeks, without clinical or radiographic progression. FDG PET imaging and immunohistochemistry were included as correlative studies. Results: 12 patients (2 GBM, 10 PC) were treated in Phase I, and 22 of 27 PC patients have been treated in Phase II. (The GBM Phase II results are reported separately). 20/32 (63%) of PC patients had received prior chemotherapy. No dose limiting toxicities were observed in Phase I, and 70 mg of RAD 001 weekly with gefitinib 250 mg qd was studied as the Phase II dose. PK parameters estimated during a 3 week single agent lead-in phase and during subsequent combined therapy suggested no clinically relevant PK interactions between RAD and gefitinib. The most common drug-related grade 3/4 toxicities were lymphopenia (28%) and elevated ALT (7%). Serial FDG PET scans showed > 25% decline in SUV uptake in 9/23 evaluable patients during the first week of treatment; of these, 3 patients showed no progression at 12 weeks. Overall, 5/29 PC patients showed no progression at 12 weeks, 3 (60%) of whom had received prior chemotherapy. Conclusions: Combination therapy with RAD 70 mg weekly and gefitinib 250 mg daily appears to be safe and is associated with modest activity in metastatic prostate cancer. Support: Novartis Pharmaceuticals, Astra Zeneca Pharmaceuticals.

[Table: see text]

A pilot study to assess the tolerability and efficacy of RAD-001 (everolimus) with gefitinib in patients with recurrent glioblastoma multiforme (GBM)

1507

Background: The majority of GBMs overexpress EGFR and have PTEN loss leading to activation of AKT signaling. mTOR is a downstream target which is blocked by RAD-001. The addition of an mTOR inhibitor to EGFR blockade by gefitinib may augment downregulation of AKT. Methods: Nineteen patients with GBM were enrolled in a phase I/II protocol open to patients with either hormone refractory prostate cancer or recurrent GBM. Patients on enzyme inducing anti-epileptic drugs (EIAEDs) were excluded, but prior treatment with an EGFR inhibitor was allowed. All patients received gefitinib 250 mg daily. Two patients enrolled in a dose escalation arm received RAD-001 30 mg or 50 mg weekly; 17 patients received the maximum tolerated dose of RAD-001 70 mg weekly. Baseline and follow-up MRIs were reviewed by a neuro-radiologist. Primary endpoints were radiographic response and progression-free survival (PFS). Results: There were 11 men and 8 women with a median age of 53 years (range 22–72) and median KPS of 80 (range 70–100). Seventeen patients (89%) were treated at their second or greater recurrence. The most frequent grade 1 and 2 toxicities were thrombocytopenia, elevated ALT, rash, anemia, leukopenia, and diarrhea. Grade 3 lymphopenia occurred in 8 patients (42%); two patients (11%) had grade 4 seizures unrelated to the study drugs. Five patients (26%) had a partial radiographic response, including one treated at 3rd recurrence, 2 treated at 4th recurrence, and one who had progressed through prior gefitinib therapy. Two additional patients (11%) had disease stabilization for greater than 4 months. Median PFS was 2.6 months. Median overall survival has not been reached, with a median follow up of 5.4 months for surviving patients. Conclusions: The combination of RAD-001 and gefitinib demonstrated activity in 37% of patients with GBM (26% responded, 11% achieved stable disease). Most subjects were heavily pre-treated and expected to have resistant disease. Because disease control was not durable, alternate dosing, or treatment earlier in the course of disease should be considered in further studying this promising combination.

[Table: see text]

Dermatologic Surgery Practice and Skin Cancer Treatment in Canada: Results of a National Survey

BACKGROUND

Although traditionally considered a medical subspecialty, dermatology has rapidly evolved over the past two decades to encompass a wide variety of cutaneous surgical procedures.

OBJECTIVE

The study was carried out to evaluate the status of dermatologic surgery practice and skin cancer treatment in Canada.

METHODS

In 2003, 550 practicing Canadian dermatologists were surveyed.

RESULTS

Two hundred fifty-one dermatologists responded to the questionnaire, with the majority practicing in an urban part-time academic, part-time private setting. Statistics are presented on the types and demographics of dermatosurgical and cosmetic procedures performed, as well as on the specific dermatosurgical therapies used in the treatment of various cutaneous malignancies.

CONCLUSIONS

The survey provides a current picture of dermatologic surgery practice and skin cancer treatment in Canada. The data suggest that Canadian dermatologists are further embracing surgical and cosmetic procedures.

V600E B-Raf requires the Hsp90 chaperone for stability and is degraded in response to Hsp90 inhibitors

The Raf family includes three members, of which B-Raf is frequently mutated in melanoma and other tumors. We show that Raf-1 and A-Raf require Hsp90 for stability, whereas B-Raf does not. In contrast, mutated, activated B-Raf binds to an Hsp90-cdc37 complex, which is required for its stability and function. Exposure of melanoma cells and tumors to the Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin results in the degradation of mutant B-Raf, inhibition of mitogen-activated protein kinase activation and cell proliferation, induction of apoptosis, and antitumor activity. These data suggest that activated mutated B-Raf proteins are incompetent for folding in the absence of Hsp90, thus suggesting that the chaperone is required for the clonal evolution of melanomas and other tumors that depend on this mutation. Hsp90 inhibition represents a therapeutic strategy for the treatment of melanoma.

A newly modified 595-nm pulsed dye laser with compression handpiece for the treatment of photodamaged skin

BACKGROUND AND OBJECTIVES

The pulsed dye laser set the standard of care for the treatment of vascular lesions, and recent modifications have enabled improved efficacy with fewer side effects. An investigational high energy, variable pulse duration pulsed dye laser has been modified to treat both vascular and pigmented lesions associated with photoaging. Each laser pulse is comprised of a sequence of eight uniform micropulses, which evenly distribute the pulse energy, effectively increasing the purpura threshold at any given fluence. Pigmented lesions are treated with a compression handpiece (CHP) that removes competing vascular target from the field, and helps to prevent purpura. This pilot study was undertaken to determine the optimum laser settings, and to investigate the ability of this device to improve vascular and pigmented lesions associated with photoaging.

STUDY DESIGN/MATERIALS AND METHODS

Twenty-four patients with photoaged skin and phototype I-III were enrolled in the study. Thirteen received treatment for vascular and pigmented lesions, and 11 subjects were treated for pigmented lesions alone. Subjects received one to three treatments at 3-4 weeks intervals, and underwent 3- and 12-week follow-up evaluation. The degree of improvement was assessed by subject evaluation as well as comparison of standardized digital photographs by three independent dermatologists. Background erythema was treated with a 12-mm spot size, at a fluence of 7 J/cm(2), and a pulse width of 10 ms. The cryogen cooling was set at 30 mseconds with a 30 ms delay. Individual telangiectasias were treated with a 5- or 7-mm spot size at fluences of 9-14 J/cm(2) and pulse widths of 6-20 mseconds. Pigmented lesions were treated using a 5- or 7-mm spot size, with energy of 9-15 J/cm(2) and a pulse width of 1.5-10 ms without cooling. The CHP had a 7-mm spot size, and fluences of 9-16 J/cm(2), and pulse widths of 1.5 or 3 ms were used in the treatment of pigmented lesions.

RESULTS

The treatment was well tolerated without the use of topical anesthetic. All subjects noted improvement in the both vascular and pigmented lesions, and were satisfied with their outcomes. Objectively, there was moderate improvement in background erythema, telangiectasia, and pigmented lesions. Three subjects who were treated with sun tans developed transient hypopigmentation and two subjects developed a transient textural change following pulse stacking for the treatment of pigmented lesions with the conventional handpiece. Purpura was noted in all patients treated for pigment with the conventional handpiece at pulsewidths less than 6 mseconds, as compared to only one that was treated with the CHP. Three patients treated in rapid succession for vascular, and then pigmented lesions with the CHP exhibited purpura, which was prevented in future treatments with 1-2 minutes of topical ice cooling between passes.

CONCLUSIONS

This novel 595-nm pulsed dye laser, with a modified pulse sequence and CHP, now has the versatility to safely treat both pigment and vascular changes associated with photoaging.

A common tumor, an uncommon location: basal cell carcinoma of the nipple and areola in a 49-year-old woman

BACKGROUND

Basal cell carcinoma (BCC) occurring on sun-protected regions is an uncommon phenomenon. BCC of the nipple is an exceedingly rare event.

METHOD

We review the literature on BCC of the female nipple and herein describe the eighth reported case in the English literature. Our patient was treated with Mohs micrographic surgery and sentinel lymph node biopsy.

CONCLUSION

BCC of the nipple are extremely rare tumors with unclear etiology. They can be aggressive and are capable of causing significant morbidity and mortality if they are neglected or improperly treated. With continued reporting of the diagnosis, treatment, and follow-up of these patients, we may gain an understanding of the pathogenesis, as well as the best method of control for these unusual tumors.

Classic Kaposi's sarcoma in the Inuit of northern Quebec

BACKGROUND

Classic Kaposi's sarcoma (KS) is predominantly a disease of eastern Mediterranean and Ashkenazi Jewish elderly men. Nevertheless, the disease has been reported to occur in people from various other ethnic and regional backgrounds.

OBJECTIVE

We report, for the first time, the occurrence of classic KS in five Inuit people living in northern Quebec, Canada.

METHODS AND RESULTS

We describe the case of a 69-year-old Inuit man with classic KS, and report four other cases of KS in the Inuit population, identified by a review of our hospital's dermatopathology records.

CONCLUSION

The discovery of classic KS in the Inuit population of northern Quebec brings with it new questions as to the origins of the KS-associated herpes virus in this population. It is our belief that the answers to these questions are in the genotype of the virus that is present in this community.

High-level expression of cancer/testis antigen NY-ESO-1 and human granulocyte-macrophage colony-stimulating factor in dendritic cells with a bicistronic retroviral vector

Tumor-specific genes delivered to dendritic cells (DCs) have been used for the generation of cytotoxic T cells (CTLs), but their application has been limited on the one hand by low viral titers resulting in low transduction efficiency and poor protein production, and on the other hand by immunogenicity of the selectable marker and poor viability of the DCs. We addressed these limitations by creating a multipurpose master vector (pMV) and cloning the tumor gene NY-ESO-1, which is highly expressed in more than 50% of advanced myeloma patients. pMV was constructed from a Moloney murine leukemia virus (Mo-MuLV)-based retroviral backbone with the following features: (1) an extended packaging signal to achieve high viral titers, (2) a splice acceptor region to facilitate protein production, (3) a nonimmunogenic selectable marker, dihydrofolate reductase-L22Y (DHFR(L22Y)), to exclude the generation of CTLs against the selectable marker, (4) an internal ribosomal entry site between the tumor-specific gene (NY-ESO-1) and the selectable marker DHFR(L22Y) for coexpression of two heterologous gene products from a single bicistronic mRNA, minimizing the possibility of differential expression of these two genes, and (5) human granulocyte-macrophage colony-stimulating factor (hGM-CSF) cDNA driven by the human T-lymphotropic virus promoter to enhance DC function and viability. Recombinant virus of pMV-NY-ESO-1 was generated with vesicular stomatitis virus G envelope protein (VSV-G) in the GP2-293 cell line for efficient transduction. We present evidence that the DC phenotype is unaltered after transduction and that more than 85% of DCs express NY-ESO-1, which secrete approximately 40 ng of GM-CSF per 10(6) DCs.

Farnesyl:protein transferase inhibitors as potential agents for the management of human prostate cancer

The effects of farnesyl:protein transferase inhibitors (FTIs) were evaluated against hormone-dependent and hormone-independent prostate cancer cell lines harboring mutant and wild type Ras. The combinations of the FTI with hormones and chemotherapy were explored. The effect of FTI on the growth of human prostate cancer lines was examined under anchorage-dependent and -independent conditions. Changes in Ras processing and cellular localization were examined by immunoblotting and immunocytochemistry. Hormone-dependent (LNCaP) and -independent (TSU-Pr1, PC3 and DU145) human prostate cancer cell lines were growth-inhibited by the FTI L-744,832 at concentrations ranging from 100 nM to 20 &mgr;M. The inhibition was accompanied by loss of protein farnesylation and with the accumulation of Ha-Ras as its unprocessed, cytosolic form. No effect on N- and Ki-Ras processing was observed. The transformed phenotype of TSU-Pr1 cells, which possess a Ha-Ras Gly-12-Val activating mutation, reverted following FTI treatment. Enhanced antitumor effects were observed when the FTI was combined with gamma-radiation, etoposide, doxorubicin, cisplatin, estramustine and the antihormone bicalutamide. In particular, the combination of taxol and FTI was synergistic for DU145 cells, a cell line that is only marginally sensitive to the FTI alone. The sensitivity of human prostate cancer cell lines to the FTI is independent of the presence of mutations of tumor suppressors, cell cycle regulators and of the activation of a variety of oncogenes, including Ras. A cell line expressing mutated Ha-Ras is particularly sensitive. Enhanced antitumor effects were observed with an anti-androgen, gamma-irradiation, and several chemotherapeutic agents. These findings support the clinical evaluation of FTIs alone or in combination as treatment for this disease. Prostate Cancer and Prostatic Diseases (2001) 4, 33-43

The histone deacetylase inhibitor suberoylanilide hydroxamic acid induces differentiation of human breast cancer cells

Histone deacetylase (HDACs) regulate histone acetylation by catalyzing the removal of acetyl groups on the NH(2)-terminal lysine residues of the core nucleosomal histones. Modulation of the acetylation status of core histones is involved in the regulation of the transcriptional activity of certain genes. HDAC activity is generally associated with transcriptional repression. Aberrant recruitment of HDAC activity has been associated with the development of certain human cancers. We have developed a class of HDAC inhibitors, such as suberoylanilide hydroxamic acid (SAHA), that were initially identified based on their ability to induce differentiation of cultured murine erythroleukemia cells. Additional studies have demonstrated that SAHA inhibits the growth of tumors in rodents. In this study we have examined the effects of SAHA on MCF-7 human breast cancer cells. We found that SAHA causes the inhibition of proliferation, accumulation of cells in a dose-dependent manner in G(1) then G(2)-M phase of the cell cycle, and induction of milk fat globule protein, milk fat membrane globule protein, and lipid droplets. Growth inhibition was associated with morphological changes including the flattening and enlargement of the cytoplasm, and a decrease in the nuclear:cytoplasmic ratio. Withdrawal of SAHA led to reentry of cells into the cell cycle and reversal to a less differentiated phenotype. SAHA induced differentiation in the estrogen receptor-negative cell line SKBr-3 and the retinoblastoma-negative cell line MDA-468. We propose that SAHA has profound antiproliferative activity by causing these cells to undergo cell cycle arrest and differentiation that is dependent on the presence of SAHA. SAHA and other HDAC inhibitors are currently in Phase I clinical trials. These findings may impact the clinical use of these drugs.

The tyrosine kinase inhibitor ZD1839 ("Iressa") inhibits HER2-driven signaling and suppresses the growth of HER2-overexpressing tumor cells

The epidermal growth factor receptor (EGFR) is commonly overexpressed in many human tumors and provides a new target for anticancer drug development. ZD1839 ("Iressa"), a quinazoline tyrosine kinase inhibitor selective for the EGFR, has shown good activity in preclinical studies and in the early phase of clinical trials. However, because it remains unclear which tumor types are the best targets for treatment with this agent, the molecular characteristics that correlate with tumor sensitivity to ZD1839 have been studied. In a panel of human breast cancer and other epithelial tumor cell lines, HER2-overexpressing tumors were particularly sensitive to ZD1839. Growth inhibition of these tumor cell lines was associated with the dephosphorylation of EGFR, HER2, and HER3, accompanied by the loss of association of HER3 with phosphatidylinositol 3-kinase, and down-regulation of Akt activity. These studies suggest that HER2-overexpressing tumors are particularly susceptible to the inhibition of HER family tyrosine kinase signaling and suggest novel strategies to treat these particularly aggressive tumors.

Modulation of Hsp90 function by ansamycins sensitizes breast cancer cells to chemotherapy-induced apoptosis in an RB- and schedule-dependent manner. See: E. A. Sausville, Combining cytotoxics and 17-allylamino, 17-demethoxygeldanamycin: sequence and tumor biology matters, Clin. Cancer Res., 7: 2155-2158, 2001

17-allyl-aminogeldanamycin (17-AAG) is an ansamycin antibiotic that binds to a highly conserved pocket in the Hsp90 chaperone protein and inhibits its function. Hsp90 is required for the refolding of proteins during cellular stress and the conformational maturation of certain signaling proteins. 17-AAG has antitumor activity in cell culture and animal xenograft models and is currently in clinical trial. It causes an RB-dependent G(1) arrest, differentiation, and apoptosis. RB-negative cells arrest in mitosis and undergo apoptosis. Hsp90 plays an important role in the cellular response to environmental stress. Therefore, we tested whether the regulation of Hsp90 function by 17-AAG could sensitize cells to cytotoxic agents. 17-AAG sensitized tumor cells to Taxol and doxorubicin. Taxanes cause growth arrest in mitosis and apoptosis. The addition of 17-AAG to cells after exposure to Taxol significantly increased both the activation of caspases 9 and 3 and apoptosis. In cells with intact RB, exposure to 17-AAG before Taxol resulted in G(1) arrest and abrogated apoptosis. Schedule dependence was not seen in cells with mutated RB, because both agents blocked cells in mitosis. Schedule- or RB-dependence was also not observed when cells were treated with 17-AAG and doxorubicin, a DNA-intercalating agent that acts on different phases of the cell cycle. These findings suggest that inhibition of Hsp90 function by 17-AAG enhances the apoptotic effects of cytotoxic agents. The sequence of drug administration and the RB status significantly influence efficacy.