Enantiomeric syntheses of conformationally restricted D- and L-2', 3'-dideoxy-2',3'-endo-methylene nucleosides from carbohydrate chiral templates

D- and L-2',3'-dideoxy-2',3'-endo-methylene nucleosides were synthesized as potential antiviral agents. The key intermediates 5-O-tert-butyldiphenylsilyl-D- and L-2,3-dideoxy-2, 3-endo-methylenepentofuranoses (20 and 33, respectively) were obtained by selective protection of the D- and L-2,3-dideoxy-2, 3-endo-methylenepentose derivatives 19 and 32 which were prepared from 1,2:5,6-di-O-isopropylidene-D-mannitol and L-gulonic gamma-lactone, respectively, and converted to 5-O-tert-butyldiphenylsilyl-D- and L-2,3-dideoxy-2, 3-endo-methylenepentofuranosyl acetates (21 and 34, respectively) or the chlorides 22 and 35. The acetates and chlorides were condensed with pyrimidine and purine bases by Vorbrüggen conditions or S(N)2-type condensation. Vorbrüggen conditions using the acetates gave mostly alpha-isomers. In contrast, S(N)2-type condensation using the chlorides greatly improved the beta/alpha ratio. From the synthesis, several D- and L-2',3'-dideoxy-2',3'-endo-methylene nucleoside analogues have been obtained, and their structures have been elucidated by NMR spectroscopy and X-ray crystallography. The synthesized D- and L-adenine derivatives were tested as substrates of adenosine deaminase, which indicated that the D-adenosine derivative 4a was a good substrate of a mammalian adenosine deaminase from calf intestinal mucosa (EC 3.5.4.4) while its L-enantiomer 10a was a poor substrate. Either the D-adenine derivative 4a or its L-enantiomer 10a did not serve as an inhibitor of the enzyme.

Locally recurrent nasopharyngeal carcinoma

PURPOSE

To assess the outcome of and determine prognostic factors for locally recurrent nasopharyngeal carcinoma (NPC) in patients treated with a second course of radiotherapy (RT).

MATERIALS AND METHODS

From 1982 to 1995, 186 NPC patients, who had initially been treated in the Department of Radiation Oncology, Chang Gung Memorial Hospital-Linkou, developed local recurrence in the nasopharynx and were re-treated with RT (>/=20 Gy). The time from the initial RT to re-treatment ranged from 8 to 136 months (median: 23 months). All patients were treated with external RT and conformal radiotherapy was used in 35 patients after 1993. Fifteen received radiosurgery as a boost treatment. The RT dose at the nasopharyngeal tumor area ranged from 20 to 67.2 Gy (median 50 Gy). Eighty-two patients received one to eight courses of cisplatin-based chemotherapy in addition to RT.

RESULTS

The 1-, 3- and 5-year survival was 54.9, 22. 1 and 12.4%, respectively. Patients whose tumor relapsed later than 2 years after the first treatment had a better survival than those with earlier relapse (3-year survival: 30.1 vs. 10.8%; P=0.015), but the difference became insignificant in patients who received >/=50 Gy. Patients without evidence of intracranial invasion or cranial nerve palsy had better survival than those with such lesions (3-year survival: 30.9 vs. 3.7%; P=0.006). A re-treatment dose >/=50 Gy yielded better survival (3-year survival: 22.8 vs. 18.5%; P=0.003). Addition use of radiosurgery may improve survival. The use of chemotherapy did not improve survival. Conformal radiotherapy resulted in significantly fewer severe complications than conventional RT.

CONCLUSIONS

A repeat course of RT for locally recurrent NPC successfully prolongs survival in a significant number of patients. Intracranial invasion and/or cranial nerve palsy and re-treatment dose affect the prognosis, with a dose of >/=50 Gy significantly improving survival. Radiosurgery boost may also improve survival. Our preliminary data indicates that conformal radiotherapy may decrease the severity of radiation-induced complications. However; longer follow-up and larger sample size is necessary to document the findings.

Imbalances between tumor necrosis factor-alpha and its soluble receptor forms, and interleukin-1beta and interleukin-1 receptor antagonist in BAL fluid of cavitary pulmonary tuberculosis

OBJECTIVES

We investigated the possibility that the large pulmonary cavity in tuberculosis (TB) lesions might result from imbalances between tumor necrosis factor-alpha (TNF-alpha) and soluble TNF-alpha receptor forms (sTNF-RI and sTNF-RII), and interleukin-beta (IL-1beta) and IL-1 receptor antagonist (IL-1RA) in sites of local inflammation.

PATIENTS AND METHODS

BAL was performed in 32 patients with active pulmonary TB, and the recovered BAL fluid (BALF) was examined for concentrations of TNF-alpha and its soluble receptor forms, IL-1beta, and IL-1RA. Patients were classified into two groups: group 1, patients with a large cavity (> or = 4 cm) on chest radiographs (n = 15); and group 2, patients with a small cavity (< 4 cm; n = 3) or no cavity (n = 14) on chest radiographs.

RESULTS

The concentrations of TNF-alpha, IL-1beta, and IL-1RA in BALF were significantly higher in group 1 patients than in group 2 patients before standardization. The difference was also statistically significant for TNF-alpha and IL-1beta after standardization with urea. Furthermore, group 1 patients had significantly higher ratios of TNF-alpha to sTNF-RI and sTNF-RII and IL-1beta to IL-1RA compared with group 2 patients.

CONCLUSIONS

These findings suggest that the relative abundance of TNF-alpha and IL-1beta associated with imbalances of secretion of soluble TNF-alpha receptor forms and IL-1RA may have caused tissue necrosis leading to cavity formation in patients with active pulmonary TB.

Tuberculous aneurysm of the abdominal aorta: endovascular repair using stent grafts in two cases

Tuberculous aneurysm of the aorta is exceedingly rare. To date, the standard therapy for mycotic aneurysm of the abdominal aorta has been surgery involving in-situ graft placement or extra-anatomic bypass surgery followed by effective anti-tuberculous medication. Only recently has the use of a stent graft in the treatment of tuberculous aortic aneurysm been described in the literature. We report two cases in which a tuberculous aneurysm of the abdominal aorta was successfully repaired using endovascular stent grafts. One case involved is a 42-year-old woman with a large suprarenal abdominal aortic aneurysm and a right psoas abscess, and the other, a 41-year-old man in whom an abdominal aortic aneurysm ruptured during surgical drainage of a psoas abscess.

The prognostic factors for patients with early cervical cancer treated by radical hysterectomy and postoperative radiotherapy

PURPOSE

This study was undertaken to evaluate the efficacy of postoperative radiotherapy (post-OP RT) and to investigate the prognostic factors for early-stage cervical cancer patients who were treated by radical surgery, and the pathological findings suggested a relatively high risk of relapse with surgery alone.

MATERIALS AND METHODS

From January 1990 to December 1995, 222 patients with stage IB-IIA cervical cancer, treated by radical surgery and a full course of post-OP RT, were included in this study. The indications for post-OP RT were based on pathological findings, including lymph node metastasis, positive surgical margins, parametrial extension, lymphovascular permeation, and invasion of more than two-thirds of the cervical wall thickness. The radiation dose of external beam was 44-45 Gy to the whole pelvis and 50-54 Gy to the true pelvis. One hundred seventy-two patients also received intravaginal brachytherapy as a local boost. The minimal follow-up period was 2 years.

RESULTS

The actuarial 5-year overall and disease-specific survival rates for all patients were 76 and 82%, respectively. The tumor control rate within the pelvis reached 94%, and distant metastasis was the major cause of treatment failure. Univariate analysis of clinical and pathological parameters revealed that clinical stage, bulky tumor size, positive lymph nodes, parametrial extension, and histologic type were significant prognostic factors. After multivariate analysis, only positive lymph nodes (P = 0.01), bulky tumor size (P = 0.02), and parametrial extension (P = 0.05) independently influenced the disease-specific survival (DSS). For patients with lymph node metastasis, the number and location of the nodal involvement significantly affected the prognosis. The 5-year DSS for patients with no, one, and more than one lymph node metastasis were 87, 84, and 61% (P = 0.0001), respectively. Patients with upper pelvic lymph node metastasis had a higher incidence of distant metastasis (50% vs 16% in lower pelvic node group, P = 0.03). In the subgroup of single lower pelvic nodal metastasis, the prognosis was similar to that of patients without lymph node involvement (5-year DSS 85% vs 87%, P = 0.71).

CONCLUSION

Our results indicate that post-OP RT can achieve very good local control in stage IB-IIA cervical cancer patients whose pathological findings show risk features for relapse after radical surgery. The prognostic factors for treatment failure identified in this study can be used as selection criteria for clinical trials to test the effects of other adjuvant treatments, such as chemotherapy. Patients with a single lower pelvic lymph node metastasis have a relatively good prognosis and may not need adjuvant treatment beyond radiation therapy.

Radiation-induced hearing impairment in patients treated for malignant parotid tumor

Radiation-induced hearing loss was evaluated in 21 patients with unilateral malignant parotid tumors treated with surgery and radiotherapy. The contralateral ear was used as a control. Eight patients (38%) were found to have a reduction in static compliance of the tympanic membrane (type B tympanogram) in the irradiated ear. By audiometry, significant hearing loss was found in 9 patients (43%). These hearing losses were mainly sensorineural, as shown by a similar reduction in both air and bone conduction, although mixed-type hearing loss existed in some patients. A statistically significant difference in incidence of 67% versus 0% (p = .0085) was noted for patients with a cochlear dose of greater than or equal to 60 Gy, in comparison to those receiving doses of less than 60 Gy. A type B tympanogram was also found to be a prognostic factor for significant sensorineural hearing loss. Patients with type B tympanograms had a much higher incidence of significant sensorineural hearing loss than those with type A tympanograms (88% versus 15%, p = .02). This study clearly shows that radiotherapy can induce significant hearing impairment, especially when the cochlear doses are higher than 60 Gy.

Rapid induction of cytokine gene expression in the lung after single and fractionated doses of radiation

PURPOSE

To investigate cytokine gene expression in the lung after single and fractionated doses of radiation, and to investigate the effect of steroids and the genetic background.

MATERIALS AND METHODS

Expression of cytokine genes (mTNF-alpha, mIL-1alpha, mIL-1beta, mIL-2, mIL-3, mIL-4, mIL-5, mIL-6, mIFN-gamma) in the lungs of C3H/HeJ and C57BL/6J mice was measured by RNase protection assay at different times after various doses of radiation. The effects of dexamethasone and fractionated radiation treatment on gene expression were also studied.

RESULTS

IL-1beta was the major cytokine induced in the lungs of C3H/HeJ mice within the first day after thoracic irradiation. Radiation doses as low as 1 Gy were effective. Responses to 20 Gy irradiation peaked within 4-8h and subsided by 24 h. With the exception of IL-1alpha and TNF-alpha, the other cytokines that were investigated had undetectable pre-treatment mRNA levels and were not radiation inducible. Similar responses were seen in C57BL/6J mice, although TNF-alpha was induced and there were some quantitative differences. Pre-treatment of C3H/HeJ mice with dexamethasone reduced basal and induced IL-1 levels, but complete inhibition was not achieved. Dexamethasone was also effective if given immediately after irradiation. Fractionated daily doses of radiation (4 Gy/day) helped to maintain cytokine gene expression for a longer period.

CONCLUSIONS

Inflammatory genes are rapidly induced in the lung by irradiation. This response cannot be readily abolished by steroid pre-treatment. Fractionated treatment schedules help to perpetuate the response.

Recurrent cervical carcinoma after primary radical surgery

OBJECTIVE

This study was undertaken to investigate prognostic factors in patients with recurrent cervical carcinoma who had undergone a primary radical hysterectomy and pelvic lymphadenectomy.

STUDY DESIGN

A retrospective analysis of 177 patients with recurrent cervical carcinoma after radical hysterectomy and pelvic lymphadenectomy for stage IB to II disease at a single institution was performed to evaluate clinicopathologic parameters, time to recurrence, pattern of failure, use of salvage therapy, and survival after recurrence.

RESULTS

The 5-year survival rate from diagnosis of recurrence in this series was 10.1%. Survival after recurrence was significantly decreased in patients with pelvic lymph node metastasis at primary surgery and adenocarcinoma-adenosquamous carcinoma histologic type. Patients with extravaginal recurrences receiving chemoradiation for recurrent cervical carcinoma had significantly better outcomes than those receiving radiation alone. Six patients who had a distant relapse at a sole site had prolonged survival after salvage therapy, which was accomplished by chemoradiation, surgery plus radiotherapy, or surgery alone.

CONCLUSIONS

Our results demonstrate the benefit of adding chemotherapy to radiotherapy in the treatment of recurrent cervical carcinoma. Salvage multimodality treatment should be offered to selected patients who have isolated relapse at a single distant site.

Light-controlled electro-optic power limiter with a Bi(12)SiO(20) crystal

An optical power limiter is a self-actuating nonlinear optical device that transmits low-intensity light and blocks high-intensity light. A light-controlled electro-optic power limiter that uses a Bi(12)SiO(20) crystal has been demonstrated. The threshold light intensity is determined by the control light and can be set to any desired level. The response time of the light-controlled electro-optic power limiter is of the order of 1 ms.

Detection of human papillomavirus types 16 and 18 mRNA in peripheral blood of advanced cervical cancer patients and its association with prognosis

PURPOSE

To evaluate the feasibility of detecting human papillomavirus E6 (HPVE6) gene mRNA in the peripheral blood of patients with locally advanced cervical cancer, and the relationship of the circulating HPV viral-specific mRNA with clinicopathologic factors and prognosis of locally advanced cervical cancer.

PATIENTS AND METHODS

The presence of types 16 and 18 HPVE6 gene mRNA was determined by reverse transcription followed by nested polymerase chain reaction. Thirty-five patients with locally advanced cervical cancer who were positive for HPV type 16 or 18 DNA were included in the study. All patients received external-beam radiation therapy followed by intracavitary brachytherapy.

RESULTS

Eighteen (51.4%) of 35 HPV DNA-positive cervical cancer patients had HPV-specific mRNA in their peripheral blood cells, compared with none of 17 HPV DNA-negative cervical cancer patients and none of 12 control volunteers. The presence of HPVE6 gene mRNA in peripheral blood was associated with bulky tumor volume (> 4 cm) and pelvic lymph node metastasis (tumor volume, P = .03; lymph node status, P = .03). After a median follow-up of 22 months, patients who were positive for peripheral-blood HPVE6 gene mRNA had a significantly higher risk of recurrence than those who were negative (10 of 18 v three of 17, P = .02; mean recurrent time, 20.7 months v 12.6 months, P = .02). There was also a statistically significant association of peripheral-blood HPVE6 gene mRNA positivity with distant metastasis (eight of 18 vone of 17; P = .01).

CONCLUSION

Results of this study seem to suggest that the presence of HPVE6 gene mRNA in peripheral blood may provide an early marker that identifies patients who are at risk for metastasis.

Preoperative prognostic variables and the impact of postoperative adjuvant therapy on the outcomes of Stage IB or II cervical carcinoma patients with or without pelvic lymph node metastases: an analysis of 891 cases

BACKGROUND

The purpose of this study was to investigate pretreatment variables that could predict prognosis and to evaluate the impact of postoperative adjuvant therapy on the outcomes of patients with Stage IB or II cervical carcinoma with or without pelvic lymph node metastases.

METHODS

Eight hundred ninety-one patients with Stage IB or II cervical carcinoma who underwent radical hysterectomy and bilateral pelvic lymphadenectomy as primary treatment at a single institution were analyzed. Potential prognostic variables were studied.

RESULTS

Among the variables that could be assessed before treatment, depth of cervical stromal invasion (determined by magnetic resonance imaging), clinical stage, tumor size, grade of differentiation, and DNA index (determined by flow cytometry) were independent predictors of outcome in multivariate analysis using a Cox regression model. Three distinct prognostic groups (low, intermediate, and high risk) were defined using these variables. Five-year recurrence free survival (RFS) rates for the low, intermediate, and high risk groups were 94.6%, 82.7%, and 62.3%, respectively (P = 0.0001), and overall survival (OS) rates were 98.4%, 84.5%, and 68.7%, respectively (P = 0.0001). Among patients with pelvic lymph node metastases who were free of parametrial extension, those who received postoperative chemotherapy or chemoradiotherapy had significantly better RFS (P = 0.017) and OS (P = 0.043) than those who received no adjuvant therapy. Among patients without pelvic lymph node metastases but at high risk of recurrence, those who received adjuvant radiotherapy had significantly better RFS (P = 0.015) and marginally improved OS (P = 0.087) compared with those who received no adjuvant therapy.

CONCLUSIONS

A model containing assessable pretreatment variables for predicting the prognoses of patients with early stage cervical carcinoma was formulated. Subsets of patients for whom postoperative chemotherapy or radiotherapy might be beneficial were identified. The data from this retrospective review may be useful when future prospective trials of the treatment of early stage cervical carcinoma are designed.

New classes of fluorinated L-nucleosides; synthesis and antiviral activity

The synthesis of 3'-fluorinated apionucleosides 7 and 2'-fluoro-2',3'-unsaturated L-nucleosides 8 via common synthon, 2-fluoro-butenolide 2, has been described. Among the newly synthesized nucleosides, L-2'-F-d4C, L-2'-F-d4FC and L-2'-F-d4A exhibit significant anti-HIV and anti-HBV activities.

Cysteine carboxyl O-methylation of human placental 23 kDa protein

C-Terminal carboxyl methylation of a human placental 23 kDa protein catalyzed by membrane-associated methyltransferase has been investigated. The 23 kDa protein substrate methylated was partially purified by DEAE-Sephacel, hydroxyapatite and Sephadex G-100 gel filtration chromatographies. The substrate protein was eluted on Sephadex G-100 gel filtration chromatography as a protein of about 29 kDa. In the absence of Mg2+, the methylation was stimulated by guanine nucleotides (GTP, GDP and GTPgammaS), but in the presence of Mg2+, only GTPgammaS stimulated the methylation which was similar to the effect on the G25K/rhoGDI complex. AFC, an inhibitor of C-terminal carboxyl methylation, inhibited the methylation of human placental 23 kDa protein. These results suggests that the substrate is a small G protein different from the G25K and is methylated on C-terminal isoprenylated cysteine residue. This was also confirmed by vapor phase analysis. The methylated substrate protein was redistributed to membrane after in vitro methylation, suggesting that the methylation of this protein is important for the redistribution of the 23 kDa small G protein for its putative role in intracellular signaling.

Regulation of c-fos gene transcription and myeloid cell differentiation by acute myeloid leukemia 1 and acute myeloid leukemia-MTG8, a chimeric leukemogenic derivative of acute myeloid leukemia 1

Both acute myeloid leukemia 1 and c-Fos are regulatory factors of hematopoietic cell differentiation. We identified that the c-fos promoter contains an acute myeloid leukemia 1 binding site at nucleotide positions -6-+14. c-fos promoter activity was induced by transient overexpression of acute myeloid leukemia 1 in Jurkat T-cells, but not by that of the short form of acute myeloid leukemia 1-MTG8, a chimeric acute myeloid leukemia 1 protein. In 32Dcl3 myeloid cells, stable overexpression of acute myeloid leukemia 1-MTG8 blocked the c-fos gene transcription and cell differentiation, but that of acute myeloid leukemia did not. These data suggest that acute myeloid leukemia 1 and acute myeloid leukemia 1-MTG8 reciprocally regulate the myeloid cell differentiation, possibly by the way of regulating c-fos gene transcription.

A practical synthesis of L-FMAU from L-arabinose

A practical synthesis of 2'-deoxy-2'-fluoro-5-methyl-beta-L-arabinofuranosyl uracil (14, L-FMAU) was developed from L-arabinose. L-Arabinose was converted to L-ribose 5, which was used for the synthesis of bromosugar 12 via 2,3,5-O-tribenzoyl-1-O-acetyl-beta-L-ribofuranose 8, which was subjected to condensation with silylated thymine and the resulting protected L-FMAU 13 was deprotected to afford L-FMAU in 14 steps in 8% overall yield.

Aldosterone directly induces Na, K-ATPase alpha 1-subunit mRNA in the renal cortex of rat

The change of blood pressure and the induction of Na, K-ATPase alpha 1-subunit mRNA have been investigated in the renal cortex of aldosterone-treated hypertensive rat. The increase of blood pressure by aldosterone-treatment for 25 days was decreased by the treatment of amiloride or spironolactone. The level of Na, K-ATPase alpha 1-subunit mRNA of the renal cortex in aldosterone-treated rat was increased than that in the control, and its increase was repressed by treatment of spironolactone, but not altered by the treatment of amiloride. This result suggests that the increase of Na, K-ATPase alpha 1-subunit mRNA in the renal cortex of aldosterone-treated hypertensive rat may be related with the direct induction of Na, K-ATPase mRNA without the increase of Na-traffic through Na-channel.

Regulation of Na,K-ATPase activity in renal basolateral membrane of 1-clip-1-kidney hypertensive rat

The changes of Na,K-ATPase activity and its regulation have been investigated in the renal cortex of 1-clip-1-kidney hypertensive rat. Ouabain-sensitive Na,K-ATPase activity (Emax) and [3H]ouabain-binding site (Bmax) in the hypertensive rat were slightly increased than those in the control. The levels of Na,K-ATPase alpha 1- and beta 1-subunit mRNA of the renal cortex in hypertensive rat were more increased than those in the control. Their increases were repressed by actinomycin-D, but not altered or more increased by cycloheximide. These results suggest that the increase of Na,K-ATPase activities and ouabain binding sites in 1-clip-1-kidney hypertensive rat may be correlated with the increases of gene expression in transcription level and/or of mRNA stability of Na,K-ATPase.

Implications of a failed prospective trial of adjuvant therapy after radical hysterectomy for stage Ib-IIa cervical carcinoma with pelvic node metastases

BACKGROUND

Lymph node metastasis is established as a poor prognostic factor in cervical carcinoma patients undergoing primary surgery. However the optimal postoperative therapy for node-positive patients remains to be defined.

MATERIALS AND METHODS

To determine the role of adjuvant therapy in stage Ib-IIa cervical carcinoma patients who had pelvic node metastases after radical hysterectomy, a single institutional randomized controlled trial with factorial design, comparing concurrent chemo-radiotherapy (CT + RT) versus chemotherapy (CT) or radiotherapy (RT) alone was conducted. Study endpoints included site of recurrence, time to recurrence, relapse-free and overall survivals, and toxicity of treatment.

RESULTS

At a median follow-up of 61 months, the 6-year relapse-free and overall survival rates of the 39 patients entered into this trial were 78.2% and 85.2%, respectively. This trial was prematurely closed due to suboptimal accrual and protocol violation. It is inconclusive regarding the efficacy of CT because of the limitation of the sample size and the imbalance of prognostic features by actual treatment. A model for risk group classification of patients with stage Ib-II cervical carcinoma with pelvic node metastases from a retrospective analysis was validated by this prospective cohort. The results of this failed trial suggest that adjuvant CT alone seemed comparable to RT alone or CT + RT in survival but was associated with significantly less morbidity.

CONCLUSION

It is warranted to consider a CT alone arm in comparison with either observation or CT + RT according to risk of recurrence in future prospective trials. However, this important issue can only be addressed by a large multicenter trial.

NGF-induced cytotoxicity in PC12 cells in a hypoglycemic environment

Surprisingly, we observed that nerve growth factor (NGF) potentiated death of PC12 cells induced by glucose withdrawal, although NGF is widely believed to exert its protective role against several types of cell death. Since either glucose withdrawal or NGF treatment increases intracellular calcium levels of target cells in many cases, we hypothesized that further increase of intracellular calcium by NGF may be a determinant factor in the NGF-mediated cell death. To test this hypothesis, we examined the effect of NGF on cell death pharmacologically by measuring cell viability and traced the changes of intracellular calcium in various conditions using a confocal laser microscope. NGF promoted cell death under a glucose-deprived condition in a manner dependent on extracellular calcium, and nifedipine, but not ryanodine, could partially block the cell death. NGF treatment augmented further intracellular calcium that had been elevated by glucose withdrawal, the event that nifedipine could block. In this study, therefore, we tentatively concluded that NGF potentiates cell death of starved PC12 cells by accelerating the initial increase of intracellular calcium through activation of a dihydropyridine-sensitive calcium channel.

Aldosterone stimulates Na,K-ATPase activity in basolateral membrane of rat kidney

The changes of Na,K-ATPase activity and its regulation have been investigated in the renal cortex and its basolateral membrane of aldosterone-induced hypertensive rat. Ouabain-sensitive Na,K-ATPase activity and [3H]ouabain-binding site (Bmax) in the hypertensive rat were significantly increased than those in the control. The levels of Na,K-ATPase alpha 1- and beta 1-subunit mRNA of the renal cortex in hypertensive rat were more increased than those in the control, and their increases were repressed by actinomycin-D. These results suggest that the increase of Na,K-ATPase activities and ouabain binding sites in aldosterone-induced hypertensive rat may be correlated with transcriptional regulation of Na,K-ATPase gene expression.

The prognostic significance of pre- and posttreatment SCC levels in patients with squamous cell carcinoma of the cervix treated by radiotherapy

PURPOSE

To investigate the prognostic significance of the pre- and posttreatment serum squamous cell carcinoma antigen (SCC) levels in patients with Stage I-IVA squamous cell carcinoma of the cervix primarily treated by radiotherapy.

MATERIALS AND METHODS

401 patients with squamous cell carcinoma of cervix primarily treated with radiotherapy (RT) were included in this study. All had preRT, and 249 patients had postRT serum SCC values. The association of pretreatment SCC level with the clinical parameters, including stage, hemoglobin (Hb) level, age, cell differentiation, and lymph node status, was assessed by univariate and multivariate analysis. The prognostic significance of pretreatment SCC level and these clinical parameters were evaluated. The impact of postRT residual induration and SCC levels on survival was analyzed.

RESULTS

1. PreRT SCC level strongly correlated with stage. After controlling for stage, only SCC levels higher than 10 ng/ml were associated with enlarged lymph nodes shown in CT scan. No association of preRT SCC level with other clinical parameters was found. 2. SCC level higher than 10 ng/ml, but not between 2-10 ng/ml, had significant impact on survival in a multivariate analysis. Stage, Hb levels (<10 g/dl) and positive lymph node shown by CT scan were also independent prognostic factors for survival. No significant difference in failure pattern in terms of local and/or distant sites was found in patients with different SCC levels. 3. Patients with residual induration and/or persistently elevated SCC level at 2-3 months after RT had a significantly higher incidence of treatment failure. Persistently elevated SCC level is a stronger predictor for treatment failure than residual induration by pelvic examination, and is associated with a higher incidence of distant metastasis. One third of patients with initial SCC level higher than 10 ng/ml had persistently elevated SCC.

CONCLUSION

Pretreatment SCC levels higher than 10 ng/ml are an independent predictor for poor prognosis in patients included in this study, and can be used as one of the prognostic factors for selection of patients for intensive treatment. Persistently elevated SCC levels after RT is a strong predictor for treatment failure. A combination of clinical pelvic examination and SCC levels provides useful information for the need of further work-up and management.

Current status of anti-HBV chemotherapy

In the past decade, significant progress has been achieved in the battle against hepatitis B virus. In addition to the immunomodulating agents such as interferon-alpha and thymosin, many novel antiviral agents have been discovered, among which nucleoside analogues are the mainstay. New-generation compounds such as 3TC and famciclovir have shown promise in the treatment of patients chronically infected by this virus, and are on the line for approval. However, viral rebound after cessation of therapy still remains a major problem. Additionally, the reports on the drug resistance to these antiviral agents suggest that combination therapy will be the eventual strategy (Bartholomew et al., 1997; Tipples et al., 1996). Therefore, developments of safe and effective antiviral agents which do not cross-resist with currently available antiviral drugs are still much needed.