DISEASE CHARACTERISTICS:

• Histologically or cytologically confirmed adenocarcinoma of the esophagus, gastroesophageal junction, or stomach

  • Squamous cell carcinoma of the esophagus also eligible
• Locally advanced, recurrent, or metastatic disease not amenable to complete surgical resection or definitive radiotherapy
• Clinically evaluable disease

• Measurable disease or clinically evaluable disease

  • Patients with inaccessible tumor tissue must have at least 1 measurable tumor deposit
• No known brain metastases

PATIENT CHARACTERISTICS:

Age

• Over 18

Performance status

• ECOG 0-2 OR
• Karnofsky 60-100%

Life expectancy

• More than 12 weeks

Hematopoietic

• Absolute neutrophil count at least 1,500/mm^3
• Platelet count at least 100,000/mm^3

Hepatic

• Bilirubin normal
• AST and ALT no greater than 2.5 times upper limit of normal

Renal

• Creatinine normal OR
• Creatinine clearance at least 60 mL/min

Cardiovascular

• No symptomatic congestive heart failure
• No unstable angina pectoris
• No cardiac arrhythmia

Other

• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use effective barrier contraception
• No prior allergic reaction attributed to compounds of similar chemical or biological composition to antisense oligonucleotides, cisplatin, fluorouracil, or other study agents
• No other concurrent uncontrolled illness
• No ongoing or active infection
• No psychiatric illness or social situation that would preclude study compliance
• Willing to undergo 2 biopsies (for patients with accessible tumor only, defined as tumors reachable by esophagogastroduodenoscopy OR metastases which can be biopsied with commonly utilized methods [e.g., CT-guided biopsy])

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No concurrent growth factors during the first course of study therapy

Chemotherapy

• No more than 1 prior chemotherapy regimen for advanced, recurrent, or metastatic disease

  • Prior significant full-dose chemotherapy (at least 2 months of therapy) during primary treatment is considered a prior regimen of chemotherapy (unless at least 6 months have elapsed since completion of treatment)
  • An additional chemotherapy regimen allowed for recurrent or progressive disease more than 6 months after the completion of prior significant chemotherapy
• At least 3 weeks since prior chemotherapy (6 weeks for mitomycin or nitrosoureas) and recovered

Endocrine therapy

• Not specified

Radiotherapy

• See Disease Characteristics
• At least 3 weeks since prior radiotherapy and recovered

Surgery

• Prior surgery allowed

Other

• More than 4 weeks since prior photodynamic therapy
• No prior oblimersen
• No other concurrent investigational agents
• No concurrent combination antiretroviral therapy for HIV-positive patients
• Concurrent photodynamic therapy for obstruction untreatable by stent, laser, or dilation allowed