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T A Tran

Publications and source records attributed to T A Tran.

At least 19 recordsLinked to original sources
PubMed2007

Effect of ultrasound-activated microbubbles on the cell electrophysiological properties.

New clinical applications of ultrasound contrast microbubbles extend beyond imaging and diagnosis toward therapeutic applications. Cell membrane permeability and the uptake of substances have been shown to be enhanced by microbubbles under ultrasound stimulation. However, the mechanisms of action of ultrasound-activated microbubbles are still unknown. The aim of our study was to examine how microbubbles and ultrasound interact with cells in an attempt to understand the sonoporation mechanism. The ruptured-patch-clamp whole-cell technique was used to measure membrane potential variations of a single cell. SonoVue microbubbles and mammary breast cancer cell line MDA-MB-231 were used. Ultrasound was applied using single-element transducers of 1 MHz. Microbubbles and cells were simultaneously video monitored during ultrasound exposure. Our results showed that, during sonoporation, a marked cell membrane hyperpolarization occurs (n = 6 cells) at negative pressures above 150 kPa, indicating the activation of specific ion channels while the cell and the microbubbles remain viable. The hyperpolarization was sustained for as long as the microbubbles are in a direct contact with the cell and the ultrasound waves are transmitted. Smaller acoustic amplitudes induced only mild hyperpolarization, whereas shutting off the ultrasound brings the cell membrane potential to its resting value. However, ultrasound alone did not affect the cell membrane potential. A similar hyperpolarization of the cell membrane was observed when a mechanical pressure was applied on the cell through a glass probe. In conclusion, the results demonstrate that microbubbles' oscillations under ultrasound activation entail modifications of the electrophysiologic cell activities by triggering the modulation of ionic transports through the plasmic cell membrane. However, only cells in direct contact with the microbubbles are impacted. The mechanisms involved are likely related to activation of specific channels sensitive to mechanical stresses (stretch-activated channels) and possibly nonspecific ion channels.

Cell Line, Tumor↗
PubMed2004

Acute vanishing bile duct syndrome after ibuprofen therapy in a child.

We report the case of a 10 year-old girl who had Stevens-Johnson syndrome and cholestasis after ibuprofen therapy. Liver histology was compatible with vanishing bile duct syndrome. She received ursodeoxycholic acid, and liver tests normalized within 7 months. This report confirms that ibuprofen may induce acute vanishing bile duct syndrome.

Acute Disease↗
PubMed2002

Lamotrigine clearance during pregnancy.

OBJECTIVE: To evaluate changes in lamotrigine (LTG) clearance before, during, and after pregnancy. METHODS: Twelve pregnancies that had complete steady-state data before, during, and after pregnancy were evaluated. Data included weight, LTG dose, and LTG blood levels at preconception, during pregnancy, and postpartum, and concomitant use of other antiepileptic drugs and their dosages. Apparent clearance (L/[kg.day]) of LTG was calculated by dose/level/weight for time points at preconception; during the first trimester, second trimester, and third trimester; and postpartum. Apparent clearance was compared between preconception and each of the three trimesters. Statistical analysis was performed using one-way analysis of variance, the Student-Newman-Keuls test, and the paired Student's t-test. RESULTS: An increase in apparent clearance (>65%) was observed between preconception and the second and third trimesters (p < 0.05). Eleven pregnancies required higher doses of LTG to maintain therapeutic levels during pregnancy. There was no significant change in apparent clearance between each trimester. A decrease in apparent clearance was observed between the last two trimesters and postpartum (p < 0.05). In the postpartum period, apparent clearances returned to the preconception baseline, and LTG doses needed to be reduced. CONCLUSION: Pregnancy increases LTG clearance by >50%. This effect occurs early in pregnancy and reverts quickly after delivery. LTG levels should be monitored before, during, and after pregnancy.

Adult↗
PubMed2001

[Leptospiroses].

Leptospirosis is a worldwide zoonosis, that is most frequently encountered in tropical and subtropical areas. In France, during the last years, its incidence has increased. Epidemiology is conditioned by a wide animal reservoir. Important clinical polymorphism makes diagnosis difficult. Laboratory abnormalities such as increased serum C-reactive protein and triglycerides and suggestive. Early diagnosis is now possible by using polymerase chain reaction methods. Early treatment with an aminopenicillin can improve prognosis which remains poor, especially in case of renal or pulmonary involvement. Pathophysiology of the disease still needs to be thoroughly studied.

Cough↗
PubMed2000

Chromosome 17 aneusomy detected by fluorescence in situ hybridization in vulvar squamous cell carcinomas and synchronous vulvar skin.

Vulvar squamous cell carcinoma (SCC) affects a spectrum of women with granulomatous vulvar diseases, human papillomavirus (HPV) infections, and chronic inflammatory vulvar dermatoses. To determine whether there is evidence of chromosomal instability occurring in synchronous skin surrounding vulvar SCCs, we investigated abnormalities in chromosome 17 copy number. Samples of SCC, vulvar intraepithelial neoplasia (VIN), and surrounding vulvar skin were obtained from all vulvar excisions performed for squamous neoplasia at Albany Medical College from 1996 to 1997. Histological categorization, fluorescent in situ hybridization (FISH) for the alpha satellite region of chromosome 17, DNA content by image analysis, and Ki-67 labeling were evaluated. Controls of normal vulvar skin not associated with cancer were used for comparison. One hundred ten specimens were obtained from 33 patients with either SCC or VIN 3 and consisted of 49 neoplastic, 52 nonneoplastic, and 9 histologically normal vulvar skin samples. The majority of SCCs (88%) and a minority (18%) of VIN 3 excisions were associated with lichen sclerosus. Normal vulvar skin controls did not exhibit chromosome 17 polysomy (cells with more than four FISH signals), whereas 56% of normal vulvar skin associated with cancer did. Moreover, the frequency of polysomy significantly increased as the histological classification progressed from normal to inflammatory to neoplastic lesions. The largest mean value and variance for chromosome 17 copy number was identified in SCCs (2.4 +/- 1.0) with intermediate values identified, in decreasing order, for SCC in situ (2.1 +/- 1.0), VIN 2 (2.1 +/- 0.8), lichen sclerosus (2.0 +/- 0.5), lichen simplex chronicus (1.9 +/- 0.4), and normal skin associated with SCC (1.8 +/- 0.4) compared with control vulvar skin (1.5 +/- 0. 05). Concordance of chromosome 17 aneusomy between cancers and synchronous skin lesions was found in 48% of patients. Loss of chromosome 17 was identified 5% of all samples and was significantly associated with women with SCC in situ (HPV-related). Both DNA content and Ki-67 labeling positively and significantly correlated with mean chromosome 17 copy number (r = 0.1, P: = 0.007). A high degree of genetic instability (aneuploidy) occurs in the skin surrounding vulvar carcinomas. As these events could be detected in histologically normal skin and inflammatory lesions (lichen sclerosus), chromosomal abnormalities may be a driving force in the early stages of carcinogenesis. Differences in chromosomal patterns (loss or gain) support the concept of at least two pathways in vulvar carcinogenesis.

Adult↗
PubMed2000

Topoisomerase II-alpha expression in melanocytic nevi and malignant melanoma.

Malignant melanoma (MM) is considered to be a chemotherapy-refractory tumor. New anti-cancer drugs (e.g. etoposide) that target DNA topoisomerases (e.g. topoisomerase II-alpha (topo IIalpha)) show activity against a wide variety of solid tumors. In this study, we investigated the frequency and rate of labeling for topo IIalpha in 163 MMs (primary and metastatic) and 67 melanocytic nevi to determine whether topo IIalpha expression is elevated in MM. Primary MM exhibited significantly more frequent topo IIalpha expression compared to benign nevi (86% vs. 56%, p=0.0001). The rate of topo IIalpha labeling in dysplastic melanocytic nevi, radial growth phase MM, vertical growth phase MM and metastatic MM revealed significant differences amongst groups and a positive covariance with advancing stage (means: 0.3, 0.5, 5, and 8 '+' cells/hpf, respectively; r=0.3, all p < or = 0.02). Topo IIalpha labeling significantly correlated with increasing mitotic activity, depth of invasion and Clark's level, diminishing tumor infiltrating lymphocytes, and poor outcome (all p < or = 0.01) in primary MM. For metastatic MM, a minority (30%) exhibited marked elevation of topo IIalpha expression. These findings indicate topo IIalpha as a potential therapeutic target and marker for MM. Immunohistochemical analysis of disseminated MM may allow for correlation with clinical response and enable selection of candidates sensitive for specific chemotherapy.

Antigens, Neoplasm↗
PubMed2000

Comparison of oncostatin M expression in keratoacanthoma and squamous cell carcinoma.

Oncostatin M (OSM) is a 28-kDa glycoprotein, produced by stimulated macrophages and T lymphocytes, that inhibits the proliferation and induces differentiation of a number of different cell lines derived from solid tumors. To determine whether keratoacanthoma (KA) is unique or a variant of squamous cell carcinoma (SCC), we compared the immunohistochemical expression of OSM in the tumor cells and peri- and intratumoral macrophages of 21 mature KAs, 7 regressing KAs, and 27 SCCs. An inverse correlation was identified between OSM tumor labeling and the density of OSM-labeled tumor-associated macrophages for KAs (r = -.4; P = .09). OSM tumor expression was significantly more frequent and more intense in KAs than in SCCs (95% versus 63%; P < .01). In contrast, the density of OSM-labeled macrophages was significantly higher in SCCs compared with mature KAs (7/3 high power fields versus 4/3 high power fields; P = .02). These OSM-positive macrophages were predominantly located at the advancing, infiltrative margins of both neoplasms. Regressing KAs demonstrated a decreased level of OSM tumor expression compared with mature KAs (53% versus 95%; P = .001), but there was no difference in density of OSM-labeled macrophages. Both the above differences and the overlapping patterns of OSM expression suggest that KAs are a variant of SCC where OSM, possibly as an autocrine factor, may mediate KA's overwhelming but not absolute tendency to involute.

Carcinoma, Squamous Cell↗
PubMed2000

Paraffin section immunophenotype of cutaneous and extracutaneous mast cell disease: comparison to other hematopoietic neoplasms.

Mast cell disease (MCD) is a rare proliferation that may be easily confused with other hematopoietic tumors. Several paraffin section antibodies immunoreact with mast cells but most are not specific. Tryptase, a specific marker of mast cells, may not be cost-effective to maintain in a laboratory because of the rarity of these lesions. This study was undertaken to assess the immunoreactivity of MCD and attempt to select a limited antibody panel for diagnosing MCD among hematopoietic tumors that morphologically mimic MCD. Immunophenotyping of cutaneous ( 10 cases) and extracutaneous (18 cases) MCD, as well as 94 other hematopoietic neoplasms, was performed on paraffin sections. All cases of MCD showed strong and diffuse positivity for CD68 and tryptase. In the vast majority of the cases, the mast cells were also positive for CD117 (27 of 28) and CD43 (25 of 27). Four cases (40%) of cutaneous MCD demonstrated a subpopulation of mast cells expressing myeloperoxidase (MPX), whereas all extracutaneous MCD were negative for MPX. Two (40%) extramedullary myeloid tumors (EMT) expressed CD43, CD68, CD 117, and MPX, but none expressed tryptase. CD43, CD68, CD117, and tryptase were expressed by 25%, 1%, 15%, and 1%, respectively, of all B-cell lymphoid neoplasms, and none expressed more than one of these four antigens. We conclude that (1) cutaneous MCDs may demonstrate a subpopulation of MPX antigen expressing tumor cells and may be confused with cutaneous involvement by myeloid leukemia if other antibodies are not used; (2) tryptase is the most specific mast cell marker among the antibodies studied; and, (3) the detection of tryptase, together with CD68, CD117, and usually CD43, is unique to MCD among hematopoietic tumors.

Adult↗
PubMed1999

Synthesis and binding properties of cyclohexapeptide somatostatin analogs containing naphthylalanine and arylalkyl peptoid residues.

We report the synthesis, binding affinities to the recombinant human somatostatin receptors, and structure-activity relationship studies of compounds related to the cyclic hexapeptide, c-[Pro6-Phe7-D-Trp8Lys9-Thr10-Phe11], L-363,301 (the numbering in the sequence refers to the position of the residues in native somatostatin). The Pro residue in this compound is replaced with the arylalkyl peptoid residues Nphe (N-benzylglycine), (S)betaMeNphe [(S)-N-[alpha(-methyl)benzyl]glycine] or (R)betaMeNphe [(R)-N-[(alpha-methyl)benzyl]glycine] and L-1-naphthylalanine is incorporated into either position 7 or 11 of the parent compound. The synthesis and binding data of the Nnal6 ([N-naphthylmethyl]glycine) analog of L-363,301 is also reported. The incorporation of the Nnal residue into position 6 of L-363,301 resulted in an analog with weaker binding affinities to all hsst receptors but enhanced selectivity towards the hsst2 receptor compared with the parent compound. The other compounds bind effectively to the hsst2 receptor but show some variations in the binding to the hsst3 and hsst5 receptors resulting in different ratios of binding affinities to the hsst5 and hsst2 or hsst3 and hsst2, respectively. The incorporation of the Nphe residue into position 6 and the Nal residue into position 7 of L-363,301 led to a compound which binds potently to the hsst2 and has increased selectivity towards this receptor (weaker binding to hsst3 and hsst5 receptors) compared with the parent compound. The analogs with beta-methyl chiral substitutions in the aromatic peptoid side chain and Nal in position 7 or 11 bind effectively to the hsst2 and hsst5 receptors. They exhibit similar ratios of binding affinities to the hsst5 and hsst2 receptors as observed for L-363,301. There are however minor differences in binding to the hsst3 receptor among these analogs. These studies allow us to investigate the influence of additional hydrophobic groups on the binding activity to the isolated human somatostatin receptors and the results are important for the design of other somatostatin analogs.

Alanine↗
PubMed1999

Conformational analyses of cyclic hexapeptide analogs of somatostatin containing arylalkyl peptoid and naphthylalanine residues.

We report the conformational analysis by 1H-NMR in DMSO and computer simulations involving distance geometry and molecular dynamics simulations of peptoid analogs of the cyclic hexapeptide c-[Phe11-Pro6-Phe7-D-Trp8-Lys9-Thr10] L-363,301 (the numbering refers to the positions in native somatostatin). The compounds c-[Phe11-Nphe6-Nal7-D-Trp8-Lys9-Thr10] (Nphe6-Nal7 analog 1), c-[Nal11-Nphe6-Phe7-D-Trp8-Lys9-Thr10] (Nal11-Nphe6 analog 2) and c-[Phe11-Nnal6-Phe7-D-Trp8-Lys9-Thr10] (Nnal6 analog 3), where Nphe denotes N-benzylglycine and Nnal denotes N-(1-naphthylmethyl)glycine, are subjected to SAR studies in order to investigate the influence of the bulky naphthyl aromatic ring on the conformation. The Nal11-Nphe6 and Nphe6-Nal7 analogs exhibit potent binding to the hsst2, hsst3 and hsst5 receptors, whereas the Nnal6 analog has decreased binding affinity to all receptors but is more selective towards the hsst2 than the other two analogs and L-363,301. The conformational search employing distance geometry, energy minimization and molecular dynamic simulations gives insight into the conformational flexibility of these analogs. The molecules adopt both cis and trans orientations of the peptide bond between residues 11 and 6. The cis isomers of these analogs adopt type II' beta-turns with D-Trp in the i + 1 position and type VIalpha beta-turns with the cis peptide bond between residues 6 and 11. The results of free and distance restrained molecular dynamics simulations at 300 K indicate that the Nphe6-Nal7 and Nal11-Nphe6 compounds adopt a preferred backbone conformation which can be described as 'folded' about residues 7 and 10. The Nnal6 analog, which binds less effectively to the hsst receptors, has a more flexible backbone structure than the Nal11-Nphe6 and Nphe6-Nal7 analogs and prefers a 'flat' structure with regard to the orientations about Phe7 and Thr10 during molecular dynamics simulations.

Alanine↗
PubMed1999

Can ploidy of prostate carcinoma diagnosed on needle biopsy predict radical prostatectomy stage and grade?

PURPOSE: Deoxyribonucleic acid ploidy correlates with the biological behavior of prostate carcinoma. However, the usefulness of ploidy on needle biopsies that show prostate cancer has not been established to our knowledge. MATERIALS AND METHODS: We retrospectively determined ploidy on needle biopsies of 159 men with prostate carcinoma treated surgically at Johns Hopkins Hospital. Ploidy was determined by image analysis of Feulgen stained slides. Needle ploidy and Gleason score were compared as prognostic tools in the prediction of grade and stage of subsequent prostatectomy. RESULTS: Of the 159 cases 98 (62%) were diploid, 16 (10%) tetraploid and 45 (28%) aneuploid. Of the diploid, tetraploid and aneuploid tumors 69, 50 and 44%, respectively, proved to be organ confined. Tetraploid and aneuploid tumors were grouped for the remaining analysis. Needle ploidy correlated significantly with pathological stage (p = 0.003). However, needle Gleason score correlated even more strongly (p <0.001), and on multivariate analysis ploidy was not further predictive of pathological stage once Gleason score was considered. Needle ploidy and Gleason score were predictive of prostatectomy Gleason score (6 or less versus 7 or greater), and on multivariate analysis ploidy was an independently significant predictor of this parameter (p = 0.04). In 13 cases (8%) there was an important grading discrepancy, in which needle ploidy would have accurately predicted prostatectomy grade. However, in 33 cases (21%) needle and prostatectomy Gleason scores were congruent, and needle ploidy did not accurately predict prostatectomy Gleason score. CONCLUSIONS: With accurate needle Gleason grading, ploidy is not helpful in predicting prostatectomy findings. However, ploidy correlates with prostatectomy stage and grade, and may be useful if accurate Gleason grading is a concern.

Aged↗
PubMed1999

Synthesis and binding potencies of cyclic hexapeptide analogs of somatostatin incorporating acidic and basic peptoid residues.

The synthesis, binding affinity, and structure-activity relationships of compounds related to the cyclic hexapeptide, c[Pro6-Phe7-D-Trp8-Lys9-Thr10-Phe11], L-363,301 (the numbering in the sequence refers to the position of the residue in native somatostatin) is reported. The Pro residue in this compound is replaced with the peptoid residues Nasp [N-(2-carboxyethyl) glycine], Ndab [N-(2-aminoethyl) glycine] and Nlys [N-(4-aminobutyl) glycine]. This series of compounds enables us to draw conclusions about the influence of positively or negatively charged residues in the bridging region on the binding affinity towards the isolated human somatostatin receptors. A loss of binding to the recombinant human somatostatin (hsst) receptors in the Nasp analog compared with L-363,301 and compared with the Ndab and Nlys analogs clearly demonstrates that the presence of an acidic residue in the bridging region is unfavorable for binding to the hsst receptors. Comparison between the Ndab analog and the Nlys analog suggests that the presence of a basic residue in the bridging region might be advantageous for binding to the hsst5 receptor provided that the residue bearing the basic group extends far enough to allow for interaction with the receptor, while the length of the basic peptoid residue does not influence binding to the hsst2 receptor. These results are useful for the design of hsst5 selective somatostatin analogs.

Chromatography, High Pressure Liquid↗
PubMed1999

Conformational analyses by 1H NMR and computer simulations of cyclic hexapeptides related to somatostatin containing acidic and basic peptoid residues.

We report the conformational analysis by 1H NMR in DMSO and computer simulations involving distance geometry and molecular dynamics simulations at 300K of peptoid analogs of the cyclic hexapeptide c-[Phe11-Pro6-Phe7-D-Trp8-Lys9-Thr10]. The analogs c-[Phe11-Nasp6-Phe7-D-Trp8-Lys9-Thr10](1), c-[Phe11-Ndab6Phe7-D-Trp8-Lys9-Thr10] (2) and c-[Phen11-Nlys6-Phe7-D-Trp8-Lys9-Thr10](3) where Nasp denotes N-(2-carboxyethyl) glycine, Ndab N-(2-aminoethyl) glycine and Nlys N-(4-aminobutyl) glycine are subject to conformational studies. The results of free and restrained molecular dynamics simulations at 300K are reported and give insight into the conformational behaviour of these analogs. The compounds show two sets of nuclear magnetic resonance signals corresponding to the cis and trans orientations of the peptide bond between residues 11 and 6. The backbone conformation of the cis isomers that we believe are the bioactive isomers of the three compounds are very similar to each other while there are larger variations amongst the trans isomers. The binding data to the isolated receptors show that the introduction of the Nlys residue in analog 3 leads to an enhancement of binding potency to the hsst5 receptor compared with analog 2 while maintaining identical binding potency to the hsst2 receptor. The Nasp6 analog 1 binds weakly to the hsst2 and is essentially inactive towards the other receptors. Comparison of the conformations and binding activities of these three analogs indicates that the Nlys residue extends sufficiently far to allow binding to a negatively charged binding domain on the hsst5 receptor. According to this model, the Ndab analog 2 cannot extend far enough to allow for binding to the receptor pocket. The loss of activity observed for the Nasp6 compound 1 indicates that the presence of a negatively charged residue in position 6 is unfavorable for binding to the hsst receptors.

Amino Acid Sequence↗
PubMed1999

Neutrophilic lobular (pustular) panniculitis associated with rheumatoid arthritis: a case report and review of the literature.

Rheumatoid nodules, which affect the subcutis around joints, are the most frequent specific cutaneous lesions of rheumatoid arthritis (RA). Panniculitis is a rarely reported and nonspecific complication of RA. We report a 42-year-old woman with seropositive RA who presented with a 2-month history of lower leg panniculitis. Biopsy of a leg nodule showed a lobular neutrophilic infiltrate with lipophages and central basophilic necrosis. In addition, focal changes of lipomembranous fat necrosis indicative of ischemic damage were identified at the margins of the lobular infiltrate. Neutrophilic lobular panniculitis is commonly detected in panniculitis secondary to bacterial infections, pancreatitis, and factitial causes. However, this pattern of panniculitis has also been reported in some cases of erythema nodosum-like lesions found in Behçet disease or bowel bypass syndrome and in rare cases of seropositive RA. These reported histologic findings fall into the spectrum of neutrophilic vascular reactions described by Jorizzo and Daniels for RA-associated dermatoses. In view of these findings. RA and related neutrophilic dermatoses (e.g., Behçet disease) should be included in the differential diagnosis of neutrophilic lobular panniculitis.

Adult↗
PubMed1999

Acquired vulvar lymphangioma mimicking genital warts. A case report and review of the literature.

A 44-year-old female developed confluent, dusky red, pruritic labial papules clinically suspected to be genital warts. She had a long-standing history of Crohn's disease with vulvar fistulae. The papular eruption developed after several bouts of cellulitis in a region of vulvar lymphedema. Shave biopsy of a papule exhibited papillated epidermal hyperplasia overlying a dermis with a 'Swiss-cheese' appearance secondary to lymphedema and superficial ectatic thin-walled vascular spaces characteristic of lymphangiectasias. Review of published cases reveals that acquired lymphangiomas often affect the vulva compared to other cutaneous sites and can be associated with surgery, radiation therapy, infection (e.g., erysipelas, tuberculosis), Crohn's disease, congenital dysplastic angiopathy and congenital lymphedema. Rather than translucent vesicles ('frog spawn') typical of extragenital cutaneous lymphangiomas, vulvar lymphangiomas often present as verrucous papules that can be mistaken for genital warts. In this case, we believe that the combination of vulvar Crohn's disease and recurrent cellulitis resulted in local lymphatic destruction, lymphedema and ultimately symptomatic lymphangiectasias that mimicked genital warts.

Adult↗
PubMed1999

Comparison of mitotic cyclins and cyclin-dependent kinase expression in keratoacanthoma and squamous cell carcinoma.

Disruption of the cell-cycle regulation through over-expression or mutation of cyclins and cyclin-dependent kinases has been implicated in carcinogenesis. In order to determine whether keratoacanthoma (KA) is unique or a variant of squamous cell carcinoma (SCC) and whether expression of mitosis-related antigens are associated with KAs' tendency to regress, we compared the immunohistochemical expression of mitotic cyclins (cyclins A and B) and their cyclin-dependent kinase p34(cdc2) in 21 KAs, 8 regressing KAs, and 28 conventional squamous cell carcinomas. KAs showed both overlap and significant differences in expression of these mitosis-related antigens compared to SCCs. Basal and parabasal pattern of expression of cyclins A and B significantly predominated in KAs in contrast to SCCs which exhibited diffuse pattern (cyclin A 86%/cyclin B 64% vs. 25%/36%, p < 0.01). However, no differences in the highest mean level of expression in 'hot spot' loci of cyclins A and B were identified comparing KAs to SCCs (19%/12% vs. 25%/13%, p > 0.05). For the cyclin-dependent kinase p34(cdc2), no differences in pattern, distribution or mean levels of expression were found. For cyclins A and B, regressing KA showed significantly more regional tumor labeling (88%/88% vs. 57%/33%, p = 0.03) and a lower mean level of immunoreactivity (5%/4% vs. 19%/12%, p = 0.001) compared to mature KAs. These findings indicate a role for mitotic cyclins in the evolution of both SCC and KA. The overlapping patterns of expression for these mitosis-related antigens suggest that KAs represent a variant of SCC that exhibit an overwhelming but not absolute tendency to involute.

CDC2 Protein Kinase↗