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PubMed1995

Hepatitis B virus precore mutant infection is associated with severe recurrent disease after liver transplantation.

The factors that predispose patients undergoing liver transplantation for hepatitis B virus (HBV) disease to severe recurrence of infection are unclear. In this study we examined the effect of pretransplantation infection with HBV and precore variant strains of HBV on posttransplantation outcome and allograft histology in 24 patients who survived more than 3 months after liver transplantation. Based on pretransplantation serum HBV DNA status as detected by the polymerase chain reaction (PCR) and direct sequencing, the 24 patients could be assigned to three groups. In group 1 there were 4 patients HBV DNA-negative before transplantation and none of these patients suffered recurrence of infection posttransplantation. In group 2, of 10 patients with pretransplantation infection with wild-type virus, 7 became reinfected, and 1 of these developed HBV-related graft failure. In group 3, 9 of 10 patients infected with precore mutant HBV strains became reinfected. However, in contrast to the patients in group 2, 7 patients in group 3 developed HBV-related graft loss, and 5 of these patients had fibrosing cholestatic hepatitis (FCH). These results indicate that infection with precore mutant strains of HBV predisposes a patient to early graft loss following transplantation.

Cholestasis↗
PubMed1999

High prevalence of CACNA1A truncations and broader clinical spectrum in episodic ataxia type 2.

OBJECTIVE: To characterize the nature of CACNA1A mutations in episodic ataxia type 2 (EA2), to search for mutations in sporadic cases, and to delineate better the clinical spectrum. BACKGROUND: EA2 is an autosomal dominant disorder characterized by recurrent acetazolamide-responsive attacks of cerebellar ataxia. The mutated gene, CACNA1A, located on chromosome 19, encodes the alpha1A subunit of a voltage-dependent calcium channel. So far, only three CACNA1A mutations have been identified-in two EA2 families and in one sporadic case. These three mutations disrupted the reading frame and led to truncated proteins. Interestingly, distinct types of CACNA1A mutations have been identified in familial hemiplegic migraine (missense mutations) and spinocerebellar ataxia type 6 (SCA-6) progressive cerebellar ataxia (expanded CAG repeats). However, except for SCA-6, these genotype-phenotype correlations relied on the analysis of very few families. METHODS: To characterize CACNA1A mutations, eight familial and seven sporadic EA2 patients were selected. All 47 exons of CACNA1A were screened by a combination of single-strand conformer polymorphism and sequencing analysis. In addition, the length of the CAG repeat has been determined in all patients. RESULTS: Seven new mutations were detected in four multiple case families and three sporadic cases. Six of them lead most likely to truncated or aberrant proteins. CAG repeat sizes were in the normal range. CONCLUSION: These data clearly establish the specificity of EA2 mutations compared with SCA-6 and familial hemiplegic migraine. Detailed clinical analysis of the mutation carriers showed the highly variable penetrance and expression of this disorder: Several of the carriers did not show any clinical symptom; others displayed atypical or permanent neurologic symptoms (such as recurrent, transient diplopia or severe, permanent, and isolated cerebellar ataxia).

Adolescent↗
PubMed2006

Membrane cofactor protein and factor I: mutations and transplantation.

Mutations in the genes for three complement regulators-complement factor H (CFH), membrane cofactor protein (MCP), and factor I (IF)-have now been described in patients with atypical HUS. The functional effects of these mutations have been studied in detail and have been shown to affect secretion, expression, and regulatory function. Genotype-phenotype correlations have shown that the majority of patients with CFH, MCP, and FI mutations develop end-stage renal failure. The outcome of transplantation is poor in patients known to have either a CFH or FI mutation, with approximately 80% of patients losing the graft to recurrent disease within 2 years. In contrast, patients known to have only an MCP mutation have a satisfactory transplantation outcome. This is expected because MCP is a transmembrane regulator and allografts will therefore be protected by wild-type MCP. Combined liver/kidney transplantation for patients known to have a CFH mutation has not been successful to date. There is optimism that in the future, targeted complement inhibitors will be of major therapeutic benefit in this condition.

Fibrinogen↗
PubMed2000

Very low levels of the mtDNA A3243G mutation associated with mitochondrial dysfunction in vivo.

We studied mitochondrial function in vivo in 2 brothers harboring the mitochondrial DNA A3243G mutation by using magnetic resonance spectroscopy. One brother presented with recurrent strokes and had a mitochondrial respiratory chain complex I defect, with 85% A3243G mutation in his quadriceps. The maximum rate of mitochondrial ATP production in his calf, measured in vivo, was reduced to 21% of the normal mean value. The second brother had mild exercise intolerance, normal muscle histochemistry, and normal respiratory chain activity in vitro. Despite a level of the A3243G mutation of only 5.95% (SD, 4.45; range, 0.7-16.1%) within single muscle fibers from the gastrocnemius muscle, the maximum rate of mitochondrial ATP production in his calf, measured in vivo, was reduced to 35% of the normal mean value. These findings suggest that there may not be a clear genetic threshold level for the expression of the A3243G mutation in skeletal muscle in vivo.

Adult↗
PubMed2005

Comparing the organophosphorus and carbamate insecticide resistance mutations in cholin- and carboxyl-esterases.

Mutant insect carboxyl/cholinesterases underlie over 60 cases of resistance to organophosphorus and/or carbamate insecticides. Biochemical and molecular data on about 20 of these show recurrent use of a very small number of mutational options to generate either target site or metabolic resistance. Moreover, the mutant enzymes are often kinetically inefficient and associated with significant fitness costs, due to impaired performance of the enzymes' original function. By contrast many bacterial enzymes are now known which can effectively detoxify these pesticides. It appears that the constraints of the genetic code and eukaryote genetic systems have severely limited the evolutionary response of insects to the widespread use of the insecticides over the last 60 years.

Animals↗
PubMed2002

Prognostic implications of routine, immunohistochemical, and molecular staging in resectable pancreatic adenocarcinoma.

Cure for ductal adenocarcinoma of the pancreas is restricted to resectable tumors, but survival after surgery is still poor. Despite apparently curative resection, these cancers rapidly recur. Thus, the present pathologic examination should be enriched by sensitive methods to detect minimal residual disease. In a prospective setting we studied the frequency of minimal residual disease after curative resection by routine histopathology, immunohistology, and polymerase chain reaction (PCR) for mutated K-ras. Furthermore, the prognostic implication of detecting of MRD was determined. Prospectively, tumor tissue and corresponding paraaortic lymph nodes were obtained from 78 patients, who underwent surgery for pancreatic head tumors between 1999 and 2001. Sixty-nine of 78 cases were diagnosed for ductal adenocarcinoma (study group), whereas nine cases were diagnosed for benign pancreatic tumors (control group). Paraaortic lymph nodes were examined in step sections by routine histopathology (hematoxylin and eosin) and immunohistology using a pan-cytokeratin antibody. DNA of the primary tumor and corresponding paraaortic lymph nodes were analyzed by PCR-based assays with respect to mutated K-ras in codon 12. The recurrence-free survival and overall survival were correlated with the results of the latter methods. In 3 of 69 patients tumor cells were detected in paraaortic lymph nodes by routine histopathology and in 5 of 69 patients by immunohistology. K-ras mutations were detected in 42 of 69 ductal adenocarcinomas (61%), whereas 12 (17%) were positive in paraaortic lymph nodes. All of the latter patients had recurrence after surgery and a significant poorer survival than those without mutated K-ras. Furthermore, paraaortic lymph nodes diagnosed for K-ras mutation were independent prognostic markers in multivariate analysis. In the control group K-ras mutations were detected in one adenoma of Vater's papilla but not in paraaortic lymph nodes. Tumor cell DNA can be detected more sensitively by the described PCR method than with hematoxylin and eosin or immunohistologic staining, leading to a higher sensitivity for detection of micrometastases. The described PCR method clearly determines subgroups of patients after curative resection with early recurrence and poor survival and could therefore enrich the pathologic examination.

Adenocarcinoma↗
PubMed2006

Ten-year multi-institutional results of breast-conserving surgery and radiotherapy in BRCA1/2-associated stage I/II breast cancer.

PURPOSE: We compared the outcome of breast-conserving surgery and radiotherapy in BRCA1/2 mutation carriers with breast cancer versus that of matched sporadic controls. METHODS: A total of 160 BRCA1/2 mutation carriers with breast cancer were matched with 445 controls with sporadic breast cancer. Primary end points were rates of in-breast tumor recurrence (IBTR) and contralateral breast cancers (CBCs). Median follow-up was 7.9 years for mutation carriers and 6.7 years for controls. RESULTS: There was no significant difference in IBTR overall between carriers and controls; 10- and 15-year estimates were 12% and 24% for carriers and 9% and 17% for controls, respectively (hazard ratio [HR], 1.37; P = .19). Multivariate analyses for IBTR found BRCA1/2 mutation status to be an independent predictor of IBTR when carriers who had undergone oophorectomy were removed from analysis (HR, 1.99; P = .04); the incidence of IBTR in carriers who had undergone oophorectomy was not significantly different from that in sporadic controls (P = .37). CBCs were significantly greater in carriers versus controls, with 10- and 15-year estimates of 26% and 39% for carriers and 3% and 7% for controls, respectively (HR, 10.43; P < .0001). Tamoxifen use significantly reduced risk of CBCs in mutation carriers (HR, 0.31; P = .05). CONCLUSION: IBTR risk at 10 years is similar in BRCA1/2 carriers treated with breast conservation surgery who undergo oophorectomy versus sporadic controls. As expected, CBCs are significantly increased in carriers. Although the incidence of CBCs was significantly reduced in mutation carriers who received tamoxifen, this rate remained significantly greater than in controls. Additional strategies are needed to reduce contralateral cancers in these high-risk women.

Adult↗
PubMed2003

Effect of strong directional selection on weakly selected mutations at linked sites: implication for synonymous codon usage.

The fixation of weakly selected mutations can be greatly influenced by strong directional selection at linked loci. Here, I investigate a two-locus model in which weakly selected, reversible mutations occur at one locus and recurrent strong directional selection occurs at the other locus. This model is analogous to selection on codon usage at synonymous sites linked to nonsynonymous sites under strong directional selection. Two approximations obtained here describe the expected frequency of the weakly selected preferred alleles at equilibrium. These approximations, as well as simulation results, show that the level of codon bias declines with an increasing rate of substitution at the strongly selected locus, as expected from the well-understood theory that selection at one locus reduces the efficacy of selection at linked loci. These solutions are used to examine whether the negative correlation between codon bias and nonsynonymous substitution rates recently observed in Drosophila can be explained by this hitchhiking effect. It is shown that this observation can be reasonably well accounted for if a large fraction of the nonsynonymous substitutions on genes in the data set are driven by strong directional selection.

Alleles↗
PubMed2002

Mutations in the thrombomodulin gene are rare in patients with severe thrombophilia.

Because thrombomodulin plays a key role in the protein C pathway, we evaluated the contribution of thrombomodulin gene mutations to venous thrombosis. We examined 38 patients with recurrent, documented thrombotic events at a young age and a positive family history. Twelve individuals with low levels of soluble thrombomodulin in plasma were also studied. Finally, the allelic frequency of the Ala455Val polymorphism was estimated in 192 patients with at least one thrombotic event and in 369 age- and sex-matched asymptomatic controls. Two mutations were identified; G/A-201, in a severely thrombophilic patient and G/T 1456, in a patient with low soluble thrombomodulin levels. The first mutation has been reported by some, but not others, to be associated with moderately reduced levels of thrombomodulin. The second was identified previously in a patient with low soluble thrombomodulin, but expression studies failed to show functional changes in the mutant. Thrombomodulin gene mutations thus appear to be rare even in highly selected thrombophilic patients, and possibly functionally irrelevant. The allelic frequency of the Ala455Val polymorphism was identical in patients and controls. Considering the lack of a phenotype and the costly screening procedure, we recommend that thrombomodulin defects be sought only for research purposes.

Adolescent↗
PubMedDate not supplied

Maspin in thyroid cancer: its relationship with p53 and clinical outcome.

The serine protease inhibitor maspin has been reported to inhibit invasiveness and motility of tumor cells. Additionally, a p53-dependent regulatory pathway of maspin in human cancer has been indicated. In a pre-study we were able to detect maspin protein in papillary thyroid carcinomas (PTC), whereas normal (tumor-free) thyroid tissue, follicular adenomas, follicular carcinomas, poorly differentiated carcinomas and undifferentiated carcinomas of the thyroid were maspin-negative. The first aim of our study was to determine the prognostic value of maspin protein expression for the recurrence-free and overall survival of PTC patients undergoing radical thyroidectomy and postoperative irradiation. Secondly, maspin expression was correlated to p53 protein expression in order to gain additional information on a possible regulatory influence of the wild-type p53 protein on maspin. An immunohistochemical approach study was performed on 68 tumor specimens. Maspin protein expression was detectable in 48 of 68 patients (71%; M+). After a median follow-up of 81 (26-117) months the median recurrence-free survival was 60 (28-117) months for M+ and 42 (11-108) months for M- (p=0.03). After 110 months 83% of patients had recurrence-free disease in M+, whereas in M- only 40% of patients were recurrence-free. The median long-term survival was 81 (42-108) months for M+ and 55 (21-99) months for M- (p=0.03). After 5 years, M+ and M- patients had a total survival of 98 and 80%, and after 9 years 90 and 60%, respectively. Mutant-type p53 expression was detectable in 17 of 68 PTC (25%). Mt p53 was positive in 1 of 47 M+ (2%) compared with 16 of 20 M- (80%, p<0.01). This study indicates that maspin protein possibly functions as a clinically relevant inhibitor of tumor progression, preventing local invasiveness and further systemic progression of papillary thyroid carcinomas. Our data hint of a p53-dependent regulatory pathway of the maspin protein in human cancer.

Adult↗
PubMedDate not supplied

Close correlation of p53 mutation to microvascular invasion in hepatocellular carcinoma.

Mutation of p53 is a poor prognostic indicator of hepatocellular carcinoma (HCC). Although poor histologic differentiation of HCC has been associated with p53 mutations, the exact reasons for unfavorable clinical outcomes in patients with HCC remain to be clarified. In this study, we evaluate the association between p53 mutation and histopathologic features of HCCs, as well as tumor recurrences and survival. We examined 20 HCCs and surrounding liver tissues from patients who underwent surgical resection, and we performed direct sequencing of p53 gene. p53 mutations were found in 9 of 20 HCCs; none were found in the surrounding liver tissue. p53 mutations were frequent in large, multinodular, and poorly differentiated HCCs. Five of 9 with p53 mutation (in contrast, none of 11 with wild-type mutation) showed microvascular invasions. Hepatocellular carcinoma recurred in 6 of 9 with p53 mutation, in contrast to only 2 of 11 with wild-type mutation. The 1-year survival rate with p53 mutation was significantly lower than that with wild-type. In conclusion, it is suggested that p53 mutations tend to be commonly associated with microvascular invasions, which may result in micrometastasis, followed by frequent recurrences.

Carcinoma, Hepatocellular↗
PubMed1997

Marfan Database (second edition): software and database for the analysis of mutations in the human FBN1 gene.

Fibrillin is the major component of extracellular microfibrils. Mutations in the fibrillin gene on chromosome 15 (FBN1) were described at first in the heritable connective tissue disorder, Marfan syndrome (MFS). More recently, FBN1 has also been shown to harbor mutations related to a spectrum of conditions phenotypically related to MFS. These mutations are private, essentially missense, generally non-recurrent and widely distributed throughout the gene. To date no clear genotype/phenotype relationship has been observed excepted for the localization of neonatal mutations in a cluster between exons 24 and 32. The second version of the computerized Marfan database contains 89 entries. The software has been modified to accomodate new functions and routines.

Animals↗
PubMed1996

[Recurrent arterial thromboembolism in hereditary hypoplasminogenaemia].

HISTORY: A 26-year-old man sustained a wasp bite 5 years ago which caused arterial embolism to the right brachial artery. Now he again had a wasp bite with allergic reaction and an arterial embolus to the left brachial artery. 2 days later, after embolectomy and heparinisation, he had a cerebrovascular accident due to an embolus to the left internal carotid artery. 15 days later, despite oral anticoagulation (Quick value 10%), he had an embolism to the left femoral artery. INVESTIGATIONS: The source of the emboli was found by echocardiography to be a spherical floating thrombus on the aortic valve. The plasminogen level was only 45-61%. His mother and sister also had a low plasminogen level, i.e. he had congenital plasminogen deficiency. TREATMENT AND COURSE: At surgery, when the thrombus had been removed, a slit-like defect was found on one of the aortic leaflets and covered with a pericardial patch. At first heparin then phenprocoumon were administered, plus 250 mg ticlopidine twice daily. There have been no further complications. CONCLUSION: As the patient's fibrinolysis activity was normal, additional, probably allergic, factors must have been present to disturb the equilibrium between thrombogenesis and fibrinolysis thus causing thrombosis at a predisposed site.

Adult↗
PubMed2003

Conditional mouse models demonstrate oncogene-dependent differences in tumor maintenance and recurrence.

Diversity in the pathophysiology of breast cancer frustrates therapeutic progress. We need to understand how mechanisms activated by specific combinations of oncogenes, tumor suppressors, and hormonal signaling pathways govern response to therapy and prognosis. A recent series of investigations conducted by Chodosh and colleagues offers new insights into the similarities and differences between specific oncogenic pathways. Expression of three oncogenes relevant to pathways activated in human breast cancers (c-myc, activated neu and Wnt1) were targeted to murine mammary epithelial cells using the same transgenic tetracycline-responsive conditional gene expression system. While the individual transgenic lines demonstrate similarly high rates of tumor penetrance, rates of oncogene-independent tumor maintenance and recurrence following initial regression are significantly different, and are modifiable by mutations in specific cooperating oncogenes or loss of tumor suppressor gene expression. The experiments make three notable contributions. First, they illustrate that rates of tumor regression and recurrence following initial regression are dependent upon the pathways activated by the initiating oncogene. The experiments also demonstrate that altered expression or mutation of specific cooperating oncogenes or tumor suppressor genes results in different rates of tumor regression and recurrence. Finally, they exemplify the power of conditional mouse models for elucidating how specific molecular mechanisms give rise to the complexity of human cancer.

Adenocarcinoma↗
PubMed2005

The relationship of molecular markers of p53 function and angiogenesis to prognosis of stage I epithelial ovarian cancer.

PURPOSE: Multiple angiogenic factors may influence tumor progression and metastasis. Several are modified by the p53 gene. We sought to identify molecular markers for high-risk stage I epithelial ovarian cancers. EXPERIMENTAL DESIGN: Seventy-seven consecutive stage I epithelial ovarian cancers were evaluated for p53, CD31 microvessel density, thrombospondin-1, vascular endothelial growth factor (VEGF), p21 immunohistochemical staining, and p53 gene mutations. Molecular marker impact upon disease-specific survival, disease recurrence, and distant recurrence was evaluated with Cox regression. RESULTS: There were 12 deaths from disease. Twelve of the 77 tumors contained p53 mutations-10 missense and 3 null (one tumor had two mutations). Fesddration Internationale des Gynaecologistes et Obstetristes substage (IA/IB versus IC; P < 0.001) and VEGF staining (P = 0.02) were significant in bivariate models with relationship to disease-specific survival. Stage (P = 0.0004), grade (P = 0.008), histology (P = 0.0025), p53 dysfunction (positive stain and/or mutation; P = 0.048), and microvessel density (P = 0.04) were significant in bivariate models with relationship to time to recurrence. In multivariate analyses among stage IC patients, failure to receive chemotherapy and microvessel density were associated with disease-specific survival, time to recurrence, and time to distant recurrence with hazard ratios of 4.8 to 44.1. CONCLUSIONS: The p53-dependent molecular markers of angiogenesis are of limited utility in developing a clinical strategy for postoperative management of stage I ovarian carcinoma. Microvessel density impacts survival and metastasis for high-risk stage IC disease. Adjuvant chemotherapy is necessary, but not sufficient, for cure of high-risk stage I epithelial ovarian cancers.

Chemotherapy, Adjuvant↗
PubMed2000

p53 alterations in recurrent squamous cell cancer of the head and neck refractory to radiotherapy.

The aim of the study was to determine the incidence of p53 alterations by mutation, deletion or inactivation by mdm2 or human papillomavirus (HPV) infection in recurrent squamous cell cancer of the head and neck (SCCHN) refractory to radiotherapy. Twenty-two tumours were studied. The p53 status of each tumour was analysed by sequencing of exons 4-9 and by immunohistochemistry. Mdm2 expression was assessed by immunohistochemistry and HPV infection was assessed by polymerase chain reaction of tumour DNA for HPV 16, 18 and 33. Fifteen (68%) of the 22 tumours studied had p53 mutations, while seven had wild-type p53 sequence. p53 immunohistochemistry correlated with the type of mutation. HPV DNA was detected in 8 (36%) tumours and all were of serotype HPV 16. Of these, five were in tumours with mutant p53 and three were in tumours with wild-type p53. Mdm2 overexpression was detected in 11 (50%) tumours. Of these, seven were in tumours with mutant p53 and four were in tumours with wild-type p53. Overall, 21 of the 22 tumours had p53 alterations either by mutation, deletion or inactivation by mdm2 or HPV. In this study, the overall incidence of p53 inactivation in recurrent head and neck cancer was very high at 95%. The main mechanism of inactivation was gene mutation or deletion which occurred in 15 of the 22 tumours studied. In addition, six of the seven tumours with wild-type p53 sequence had either HPV 16 DNA, overexpression of mdm2 or both which suggested that these tumours had p53 inactivation by these mechanisms. This high incidence of p53 dysfunction is one factor which could account for the poor response of these tumours to radiotherapy and chemotherapy. Therefore, new therapies for recurrent SCCHN which either act in a p53 independent pathway, or which restore p53 function may be beneficial in this disease.

Adult↗
PubMed1993

Genotypic classification of colorectal adenocarcinoma. Biologic behavior correlates with K-ras-2 mutation type.

BACKGROUND: New measures enabling better prediction of biologic behavior of large bowel cancer are highly desirable. One hundred ninety-four consecutive primary, recurrent, and metastatic colorectal adenocarcinomas, accessioned during 1991 at Rhode Island Hospital, were classified according to the presence and specific type of K-ras-2 point mutation. METHODS: An integrated histopathologic-genetic approach was used to detect mutations starting with minute, topographically selected, tissue samples from formaldehyde-fixed, paraffin-embedded specimens. RESULTS: Each colorectal adenocarcinoma exhibited either no or only one of seven specific types of K-ras-2 mutation. The mutation type of each primary tumor was present consistently in its metastatic deposits. Thirty-five percent of primary colorectal adenocarcinomas were found to be mutated (42 of 119). A significantly higher mutation rate (65%) was seen in lymphogenous-hematogenous metastases as a group (35 of 54; P < 0.005). By contrast, 22% of anastomotic recurrences and transcoelomic metastasis were mutated (4 of 18). Twenty-eight percent of adenocarcinomas with invasion limited to muscularis propria (Tis, T1, T2) were mutated (16 of 57), compared to 41% for more deeply invasive tumors (T3, T4; 26 of 63). When colorectal adenocarcinomas were analyzed by specific K-ras-2 mutation type, it was found that codon 13 mutated tumors did not progress to local or distant metastasis (P < 0.01). Tumors having a codon 12 valine substitution did not metastasize beyond pericolonic-perirectal lymph nodes. In contrast, colorectal cancers with codon 12 aspartic acid substitutions accounted for most of the distant hematogenous deposits (P < 0.01). Tumors with normal K-ras-2 accounted for most intraperitoneal deposits. CONCLUSIONS: Genotyping of colorectal adenocarcinoma by K-ras-2 status can identify subsets of patients likely to pursue indolent and aggressive forms of disease. The integrated histopathologic-genetic approach outlined is feasible for use in diagnostic pathology, providing information that together with clinicopathologic staging may individualize and optimize treatment.

Adenine↗
PubMed2000

A phase I study of Onyx-015, an E1B attenuated adenovirus, administered intratumorally to patients with recurrent head and neck cancer.

An E1B 55 kDa gene-deleted adenovirus, Onyx-015, which reportedly selectively replicates in and lyses p53-deficient cells, was administered by a single intratumoral injection to a total of 22 patients with recurrent head and neck cancer. The objectives of this Phase I study were to determine the safety, feasibility, and efficacy of this therapy and determine any correlation to p53 status. Six cohorts were investigated with a dose escalation from 10(7)-10(11) plaque-forming units. Toxicity was assessed using NCIC criteria. Tumor response was assessed by clinical and radiological measurement. Blood samples were taken to detect adenovirus DNA and neutralizing antibody to adenovirus. Tumor biopsies were taken to detect adenovirus by in situ hybridization. Treatment was well tolerated, with the main toxicity being grade 1/2 flu-like symptoms. Dose-limiting toxicity was not reached at the highest dose of 10(11) plaque-forming units. Twenty-one of the 22 patients treated showed an increase in neutralizing antibody to adenovirus. In situ hybridization showed viral replication in 4 of 22 patients treated, all of whom had mutant p53 tumors. Using conventional response criteria, no objective responses were observed. However, magnetic resonance imaging scans were suggestive of tumor necrosis at the site of viral injection in five patients, three of whom were classified using nonconventional criteria as partial responders, and two of whom were classified using nonconventional criteria as minor responders. Of these five cases, four had mutant p53 tumors. The response duration for the three partial responders was 4, 8, and 12 weeks. An additional eight patients had stable disease in the injected tumors lasting from 4-8 weeks. These preliminary results show that intratumoral administration of Onyx-015 is feasible, well tolerated, and associated with biological activity. Further investigation of Onyx-015, particularly with a more frequent injection protocol and in combination with systemic chemotherapy, is warranted.

Adenovirus E1B Proteins↗